U.S. Customs and Border Protection, a component of the Department of Homeland Security, has the primary responsibility for securing the nation’s borders. The U.S. Border Patrol is the uniformed enforcement division of CBP responsible for border security between designated official ports of entry into the country. According to the Border Patrol, its priority mission since the terrorist attacks of September 11, 2001, has been to prevent terrorists and terrorist weapons from entering the United States between official ports of entry. In addition, the Border Patrol has a traditional mission of preventing illegal aliens, smugglers, narcotics, and other contraband from entering the country, as these activities directly affect the safety and security of the United States. Border Patrol agents generally report to Border Patrol stations and substations in each of these sectors at the start and end of their workdays; these stations function much as police stations do for police personnel around the country. The number of stations and substations varies widely by sector. The Border Patrol’s fiscal year 2005 budget was about $1.4 billion. As of March 2005, the Border Patrol had 10,817 agents nationwide; 6,129 (57 percent) were located in the 9 Border Patrol sectors along the southwest border. About 10 percent of the Border Patrol’s agents nationwide are assigned to interior traffic checkpoints in the southwest border sectors, according to the Border Patrol. Permanent and tactical interior traffic checkpoints are generally located on major and secondary roads, usually 25 to 75 miles inland from the border. These interior checkpoint locations are chosen by the Border Patrol to maximize the likelihood that illegal entrants who have managed to evade border defenses and patrols will have to pass through the checkpoints in order to get to major U.S. population centers. Although tactical checkpoints are mobile and may move daily or weekly, as needed, they must provide adequate advance notice to motorists that a checkpoint has been set up and is in operation. This is typically done by using orange traffic cones and large, visible signs positioned in advance of the checkpoint location. Permanent checkpoints, by virtue of their permanence and large traffic signs, meet these criteria for advance notice and visibility. Figure 1 shows the topography, interstate highways, and some major secondary roads along the southwest border. The legacy Immigration and Naturalization Service (INS) Border Patrol began implementing a strategy called Operation Hold-the-Line in 1993, to incrementally increase control of the Southwest border in four phases by making it so difficult and costly for aliens to attempt illegal entry that fewer individuals would try. The four-phased approach involved adding resources along the Southwest border, starting with the areas that had the highest known levels of illegal alien activity, which at that time were the San Diego, California; El Paso, Texas; and McAllen, Texas, regions. Although INS accomplished its goal of shifting illegal alien traffic away from these areas, the shift was achieved at a cost to both illegal aliens and INS. In particular, rather than being deterred from attempting some illegal entry, many aliens have instead risked injury and death by trying to cross mountains, deserts, and rivers, primarily in Arizona and in particular in the Tucson sector. These conditions, which the Border Patrol said continue to the present day, prompted INS and now CBP to warn aliens about the dangers of crossing illegally, as well as to establish search-and- rescue units. In effect, and contrary to the expectations of INS, the strategy led to a significant increase in illegal immigration through the Tucson sector, despite its topography and climate, as indirectly measured by total apprehensions, which increased nearly sevenfold in this sector over the period of fiscal years 1993 to 2000. In contrast, during the same period, total apprehensions for the eight other southwest sectors combined decreased by about 28 percent. The largest single decrease was in the San Diego sector, where apprehensions fell by almost three-fourths over 1993- 2000. Nationwide, Border Patrol apprehensions at all locations (including on the border, near the border, and at interior checkpoints) of illegal aliens over the last 4 years have varied from about 1.3 million in fiscal year 2001, to 955,000 in fiscal year 2002, 931,000 in fiscal year 2003, and over 1.1 million in fiscal year 2004. Figure 2 shows the total annual apprehensions of illegal immigrants at all locations in each of the 9 southwest Border Patrol sectors reported for fiscal years 2001 to 2004. As shown, the Tucson sector has had the largest numbers of apprehensions since fiscal year 2001, which Border Patrol officials attribute in part to the legacy INS’s strategy to deter illegal entry between the official ports of entry in the sectors that had the highest estimated illegal immigration in the early and mid-1990s, the San Diego, California, and the Texas sectors of El Paso and McAllen. It is apparent that in recent years far more apprehensions of illegal aliens have occurred in the Tucson sector than in the 8 other sectors. When establishing checkpoints, the Border Patrol must take into account court decisions ruling on the parameters of immigration officers’ authority to conduct inquiries concerning illegal aliens. The legal authority of immigration officials to establish permanent checkpoints and stop vehicles transiting through them has been confirmed by the Supreme Court in United States v. Martinez-Fuerte. The Supreme Court ruled that government officials may stop vehicles at permanent interior checkpoints for brief questioning of the driver and passengers without reasonable suspicion. The Court held that it was constitutional for the Border Patrol, after routinely stopping or slowing automobiles at a permanent checkpoint, to refer motorists selectively to a secondary inspection area for questions about citizenship and immigration status on the basis of criteria that would not sustain a roving patrol stop. The Court determined that the constitutional interests of motorists at these checkpoints were not violated, for a number of reasons. It found that the checkpoints, with flashing lights and warning signs, provided advance notice to motorists of an official roadblock that was applicable to all motorists. Motorists were not taken by surprise, as they knew, or could find out, the location of the checkpoints. Furthermore, the Court concluded that the regular manner in which established checkpoints were operated was visible evidence that the stops were duly authorized. An organization that specializes in immigration issues has estimated that the number of people who have successfully entered the United States illegally has averaged roughly half a million per year since 1990 and that the number of illegal aliens residing in the United States has grown in recent years from about 8.4 million in April 2000 to about 11 million in March 2005. The Border Patrol uses permanent and tactical checkpoints in 8 of its 9 southwest sectors as part of a multilayered enforcement strategy to deter and defend against potential terrorists and their weapons, contraband smugglers, and persons who have entered the country illegally. Corresponding to their different roles in the Border Patrol’s enforcement strategy, permanent and tactical checkpoints have different capabilities. Permanent checkpoints have the advantage of physical infrastructure, which provides a wide range of logistical, communication, suspect questioning and detention, and equipment deployment and storage capabilities, as well as adequate shade and cages for canines. Tactical checkpoints have the advantage of mobility, which gives the Border Patrol the capability to respond quickly to emerging trends, intelligence, or national security threats. According to the Border Patrol, permanent checkpoints are most effective when supplemented by tactical checkpoints, which are generally used on secondary roads to cut off access to those seeking to evade permanent checkpoints on major arteries. This is not the case in the Tucson sector, where legislative language has prohibited the construction of checkpoints since fiscal year 1999. Moreover, starting in mid-2002, and through fiscal year 2004, the Border Patrol relocated or closed checkpoints in the Tucson sector on a regular basis, such as at least once every 7 days. The result has been a sector of nonpermanent checkpoints that lack the advantages of either permanent or tactical checkpoints, and which the Border Patrol states have degraded the Border Patrol’s ability to fulfill its mission in the Tucson sector. The Border Patrol uses interior traffic checkpoints as a third layer of defense and deterrence against potential terrorists and their weapons, contraband smugglers, and persons who have entered the country illegally. According to the Border Patrol, permanent and tactical checkpoints are part of an integrated, multilayered enforcement strategy intended to achieve two key law enforcement objectives: (1) to increase the likelihood of detection and apprehension of illegal entrants of all types, and thereby to deter other potential illegal entrants from attempting to enter the country, who might otherwise believe that successfully crossing the border would mean that there were no further barriers to them, and (2) to deter illegal entrants from transiting through permanent checkpoints on major roadways, through fear of detection, and thereby to cause them to use less traveled secondary roads on which the Border Patrol is able to stop all or almost all vehicles (because of much lower traffic volume), making illegal entrants more visible and easier to detect and apprehend. Procedures at both permanent and tactical checkpoints involve slowing or stopping traffic as vehicles proceed through the checkpoint. As traffic slows, Border Patrol agents use visual cues and canines trained to locate drugs and hidden persons to determine whether to wave the vehicle through, or stop the vehicle, question the occupant(s), and determine whether a more thorough secondary inspection is required. Permanent checkpoints are placed at locations that are intended to maximize the chances to detect illegal immigrants and smugglers who have crossed the border illegally and who are seeking to reach large population centers, such as Los Angeles, California, or Phoenix, Arizona. Where possible, according to the Border Patrol, permanent checkpoints are placed after several highways or roads join, so that anyone intending to exit the area into the interior of the country must transit them. Permanent checkpoints’ physical infrastructure gives them different capabilities than tactical checkpoints. For example, permanent checkpoints facilities are equipped with technology and computers connected to national law enforcement databases to help identify suspects, research criminal histories, and cross check terrorist watch lists. They also offer greater physical safety to those working at them, by virtue of better signage, lighting, and larger shoulder areas to stand out of the way of traffic, and many of them are paved and have protective concrete barriers. In addition, permanent checkpoints have supporting infrastructure and procedures intended to reduce the ability of illegal entrants from circumventing the checkpoints. These include remote video surveillance, electronic sensors, and agent patrols in the vicinity of the checkpoints. Among the resources that are generally found at permanent checkpoints are: Computers hardwired into national law enforcement databases, such as the Federal Bureau of Investigation’s (FBI) Integrated Automated Fingerprint Identification System (IAFIS) system, to provide identity checks. Figure 3 shows a fingerprint reading machine at a permanent checkpoint as it scans a fingerprint and then transmits the information to a centralized database via high-speed communications primarily available through a hardwired, secure line. Electrical and water utilities Permanent tollbooth-like structures that provide cover from the weather, including shade for agents and canines Buildings with room for processing and detention of persons suspected of smuggling or other illegal activity Permanent, large communication towers that permit radio communication to other Border Patrol facilities and national law enforcement authorities Permanent lighting for night and poor weather conditions Vehicle lifts to raise vehicles to inspect under them, and the area required for the lifts, as shown in figure 6. Tactical checkpoints are intended to supplement permanent ones by monitoring and inspecting traffic on secondary roads that can be used to evade the permanent checkpoints. For example, the Temecula permanent checkpoint in the San Diego sector maintains up to eight tactical checkpoints to inspect vehicles traveling on back roads in the hills around the permanent checkpoint on I-15. Tactical checkpoints are intended to be mobile and set up for short-term use only. They are relocated by the Border Patrol in order to respond to intelligence on changing patterns of contraband smuggling and routes being used by illegal aliens. According to the Border Patrol, the combination of permanent and supplemental tactical checkpoints is intended to both detect persons who have entered the country illegally and to increase the chances of detecting and apprehending contraband smugglers and illegal aliens who seek to avoid permanent checkpoints and instead use less traveled routes. On these less traveled routes, with comparatively low traffic volume of as little as a few hundred vehicles daily, the Border Patrol is able to stop every car and closely observe the occupants, as well as question them. This increases the likelihood of detecting illegal entrants, while on heavily traveled highways, only a small percentage of vehicles can be subjected to this level of inspection, in order to avoid creating long traffic delays. In contrast to the resources that are typically deployed at permanent checkpoints, tactical ones, by virtue of their mobility, do not have large fixed facilities or hardwired communications. They do, however, offer the element of flexibility, by virtue of their mobility. Tactical checkpoints generally consist of a few Border Patrol vehicles, used by agents to drive to the location; orange cones to slow down and direct traffic; portable water supply; a cage for canines (if deployed with the checkpoint); portable rest facilities; and warning signs. Some may also have portable lighting, if operated at dusk or night. If persons are detained at a tactical checkpoint, some of the agents must leave the checkpoint to transport them back to a Border Patrol station for positive identification. Our observations of tactical checkpoints showed that most equipment has to be towed or carried to the checkpoint for it to operate, and then has to be removed when it relocates. According to the Border Patrol, this increases wear and tear on the equipment and absorbs time to hitch up, tow, set up, dismantle, and tow the equipment back to a Border Patrol station or to an alternate tactical checkpoint. Figure 7 shows a tactical checkpoint on Sandia Creek road, in a rural area near Temecula, California, that was used to supplement the permanent checkpoint on I-15. While the changing locations of tactical checkpoints would appear to offer the potential element of surprise, we were told by the Border Patrol that the smugglers of aliens and contraband could use cell phones and communications networks to alert confederates of the presence of checkpoints within minutes of their being relocated. The Border Patrol provided us with information that confirmed that smugglers of aliens and contraband observed some checkpoints and reported on their activities to their confederates. According to the Border Patrol, smugglers know within minutes about the closure of a checkpoint. For fiscal years 1999-2004, annual appropriations acts made no funds “available for the site acquisition, design, or construction” of any Border Patrol checkpoint in the Tucson sector. Since the Tucson sector had no permanent checkpoints at the time the prohibition was first imposed, the effect of this restriction was that no permanent checkpoints could be planned or constructed in this sector. According to the Border Patrol, it used a combination of roving patrols and temporary checkpoints in the sector that remained at the same location for long periods but did not have permanent infrastructure. This arrangement was adequate, the Border Patrol stated, until the late 1990s, when the volume of illegal entrants into the sector increased substantially as its overall strategy to greatly reinforce the border in urbanized areas took effect in San Diego, California; El Paso, Texas; and McAllen, Texas. The fiscal year 2003 and 2004 Appropriations Acts also added a provision requiring that the checkpoints in the Tucson sector be relocated “at least once every 7 days in a manner designed to prevent persons subject to inspection from predicting” their location. Since permanent checkpoints could not be built under these restrictions, and temporary ones had to be relocated at least once every 7 days, the checkpoints functioned as hybrids, or what we refer to as nonpermanent checkpoints that had neither the advantages of the physical infrastructure typical of permanent ones nor the flexibility of tactical checkpoints to respond to intelligence information. Such checkpoints do not have permanent infrastructure and hence lack the multiplicity of capabilities typically associated with permanent checkpoints in other sectors. At the same time, they also do not have tactical flexibility because they are generally kept at the same locations, which have been chosen by the Border Patrol in part for both safety and legal considerations. The checkpoint locations need to have adequate shoulder space on which to place the equipment needed to maintain the checkpoint, such as a small trailer, water tanks, portable lights and generators, as well as space to conduct secondary inspections of vehicles ordered to pull over. The locations also need to have sufficient space to place signs in advance of the checkpoint to notify vehicles of the checkpoint’s location (to comply with legal decisions) and cannot be placed after or around sharp curves that might force vehicles to come to a sudden stop upon notice of the checkpoint. In addition, the checkpoint locations are chosen by the Border Patrol to maximize the likelihood that illegal entrants would have to transit through them in order to move northward. Depending on the criticality of their original location in terms of road networks and smuggling routes, relocating these checkpoints can reduce their effectiveness in monitoring vehicular traffic. (See app. III, fig. 14, for a map of the sector and its checkpoints.) To support these nonpermanent checkpoints, the Tucson sector operates tactical checkpoints periodically, as occurs in other sectors with permanent checkpoints. The fiscal year 2005 Appropriations Act limited the funding prohibition to only construction, thus allowing the use of funds for site acquisition and design. Further, this act directed CBP to conduct a study of locations for proposed permanent checkpoints within the Tucson sector. In addition, the 2005 Act changed the requirement to relocate checkpoints to “at least an average of once every 14 days.” According to the Border Patrol, the phrase “an average” gave it more flexibility in determining checkpoint operating schedules than the previous years’ requirement of “at least once every 7 days.” As a result, in fiscal year 2005, the Patrol operates the checkpoint on I-19 for 14 days, closes it for 8 hours, and then reopens it for 14 days. In addition, the Patrol has kept the checkpoint at the more northern kilometer post (KP) 42 location, because, it stated, moving it south to the KP 25 location every 7 days had permitted illegal immigrants to wait until KP 42 closed, and to then move north. At other checkpoints in the Tucson sector, the Patrol has maintained varying opening and closing schedules, which it stated were in conformity, in its view, with the “average of once every 14 days” language. However, as reported by the House Appropriations Committee, the fiscal year 2006 appropriations bill would restore the 7-day relocation requirement. Also, it provides that no funds may be used for site acquisition, design, or construction of permanent checkpoints in this sector. Prior to the implementation of INS’s southwest border strategy in 1993, the Tucson sector had a smaller volume of illegal alien traffic relative to the San Diego and El Paso sectors, as indirectly measured by apprehensions. In fiscal year 1993, the Tucson sector had less than one-fifth as many apprehensions as the San Diego sector, and less than one-third those in the El Paso sector. As the strategy unfolded, the San Diego and El Paso sectors became more difficult for illegal aliens to cross, while the volume of illegal traffic in the Tucson sector increased nearly sevenfold over the period of fiscal years 1993-2000, as measured indirectly by sectorwide apprehensions. This increase in illegal activity, as well as a general increase in legitimate vehicular traffic, led the Border Patrol to consider a more permanent presence for checkpoints in the Tucson sector, where it had previously operated only tactical checkpoints, to provide the range of facilities offered by permanent checkpoints. The Border Patrol started implementing the 7-day relocation requirement in June 2002, as noted above. Patrol officials told us that where feasible, taking safety and operational strategy into account, they alternated the sites of nonpermanent checkpoints along the same route in the Tucson sector. The Border Patrol was able to establish nonpermanent checkpoints among alternate sites on two such routes. However, for 3 of the 6 checkpoints in the sector, safety factors precluded use of other locations on the same route, and the Border Patrol closed the checkpoints for 7 days. (One checkpoint of the 6 closes each night and is replaced with roving vehicle patrols, because of the very sparse population of the region in which it is located.) The 7-day relocation rule was changed to “at least an average of once every 14 days” in fiscal year 2005 appropriations legislation. The Border Patrol told us that it did not seek to evade compliance with the intent of the relocation rule by opening an alternative checkpoint just a short distance from the first one, or by closing for just a few hours. It did attempt to close and open for a few days at a time, they said, to try to confuse illegal aliens and contraband smugglers. However, officials stated that this was not productive, as the smugglers monitored the checkpoint activities so closely. According to Border Patrol officials, the funding prohibition on constructing checkpoints in the Tucson sector, in combination with the mandated relocation on a regular basis, allows smugglers and illegal aliens to further their entry into the United States with reduced interdiction risk. Table 1 shows the variations followed by the Border Patrol in operating the nonpermanent checkpoints in the Tucson sector. According to Border Patrol officials, contraband smugglers and illegal aliens typically wait until they learn from confederates that a checkpoint is in the process of being relocated or has been closed, and then use this downtime to further their illegal entry. Border Patrol officials told us that in today’s environment, they are up against increasingly sophisticated smugglers who use radios, cell phones, global positioning systems, and other high-technology equipment to watch agents’ movements and alert each other when checkpoints are moved or closed. On highway I-19, the interstate highway that runs from Nogales, Arizona, on the border, directly north to Tucson, the Border Patrol alternated between two locations for nonpermanent checkpoints, at KP 42 and at KP 25, at congressional staff instruction (for the last quarter of fiscal year 2002), and then in conformity with the legislative restrictions for fiscal years 2003 and 2004. When the northern one (KP 42) was open, however, the Border Patrol told us that illegal aliens and smugglers who had made it over the border then waited in communities south of it, but north of KP 25. (See app. III, fig. 14 for a sector map that shows these locations.) When the checkpoint at KP 42 closed and moved down to KP 25, the illegal entrants who waited north of KP 25 (but south of KP 42 while open) were able to move with reduced interdiction risk, because there was no longer a checkpoint north of them. In fiscal year 2005, as noted above, the Border Patrol has maintained the checkpoint at the more northern KP 42 location, to reduce the potential for illegal entrants taking advantage of the relocation that occurred in previous years. In addition, the checkpoint is kept open for 14 days, then closed for 8 hours, and then reopened for 14 days. The Border Patrol stated that it believes that this schedule conforms to the fiscal year legislative language that requires that Tucson sector checkpoints be relocated an average of at least once every 14 days. Border Patrol officials told us that without the infrastructure typical of the Patrol’s permanent checkpoints in others sectors, the Tucson sector cannot perform the full range of enforcement functions. For example, without access to national databases, suspects detained at the sector’s nonpermanent checkpoints cannot be readily identified and must be transported by an agent or agents to a Border Patrol station with database access, in order to determine if the persons should be detained. Further, the nonpermanent Tucson checkpoints lack paved, adequately large, level, off-road shoulder areas to deploy vehicle lifts or VACIS trucks required to examine underneath and inside vehicles. According to the Border Patrol, because detention facilities at these checkpoints are small rooms in mobile trailers, with weak internal doors and locks, they can be insufficient in size and security. (See photo in fig. 8.) Upon apprehension of a suspect or suspects, Border Patrol agents from the checkpoint must transport them to a station with adequate facilities for detention and processing, as would be found at typical permanent checkpoints elsewhere. The Border Patrol stated that sending an agent or agents to a station with suspects is an inefficient use of personnel and can cause the nonpermanent checkpoint to close because of personnel shortages. Figure 8 shows photographs of the nonpermanent checkpoint operated on I-19 in the Tucson sector at KP 42, with limited facilities, located under an overpass to provide shelter from sun and weather, and lacking a paved shoulder for vehicles pulled over for further inspection. Although total apprehensions and contraband seizure data are available for interior checkpoints, some of the benefits—such as deterrence of potential contraband smugglers or of persons contemplating illegal entry into the United States—and costs of traffic checkpoints are difficult to quantify because deterrence is difficult to measure and cost data are not maintained separately by the Border Patrol for permanent or tactical checkpoints. Studies or reports on checkpoint benefits and costs have also not been performed by the Border Patrol. Of the less quantifiable benefits that can be described, we were told that intelligence debriefings of apprehended aliens and smugglers testify to the deterrent effects of interior checkpoints. In addition, local citizens and community groups with whom we met who live near or in the vicinity of interior checkpoints are generally supportive. However, this support is not universal. The most readily available data on the benefits of interior checkpoints are the drug seizure and apprehension data recorded by the Border Patrol on a daily basis at its checkpoints and stations. In fiscal year 2004, for example, the Border Patrol reported that the southwest interior checkpoints, which were staffed by about 10 percent of Border Patrol agents in those sectors, were responsible for 96,000 illegal alien apprehensions, or 8 percent of all Border Patrol apprehensions, and for seizure of 418,102 pounds of marijuana and 10,853 pounds of cocaine in fiscal year 2004, or about 31 percent of the marijuana and about 74 percent of the cocaine seized nationally by the Border Patrol. In addition to the benefits of seizing contraband, and mitigating the smuggling of humans, there were at least six incidents reported to us where individuals with suspected ties to terrorism were identified when transiting a Border Patrol interior checkpoint and appropriate actions were coordinated with the FBI. Intelligence debriefings of smugglers and illegal aliens and reports of increased smuggling costs provide some evidence of checkpoints’ deterrent effect. Information from debriefings suggests that interior checkpoints deter some persons from attempting to go through them, and also push them into rural areas that are more difficult to transit and where they are more easily identifiable among a lower volume of traffic. In addition, the presence of effective checkpoints can contribute to increased smuggling costs, also possibly serving as a deterrent, according to the Border Patrol. In the San Diego sector, for example, we were told by the Border Patrol that smuggling fees charged to Mexicans and others had increased fivefold in recent years (to about $1,500 per person), because of the perceived difficulty of breaching border defenses and of transiting through interior checkpoints undetected. It is difficult, however, to separate out the contribution to deterring potential illegal entrants from entering the United States of increases in smuggling fees that are due to better line watch and line patrol border operations versus those cost increases that could be attributed to vigilance at interior checkpoints. (We did not validate the Border Patrol’s statements with regard to increased smuggling fees.) Evidence for the deterrent effects of checkpoints was reported in a 1995 INS study which found that that smugglers and illegal aliens adjust their transit routes because they are well aware when checkpoints are open and closed. The 1995 study reported on a test of interior checkpoint operations in which the permanent checkpoint on I-5, near San Clemente, California, was closed several times, in order to determine the impact of the checkpoint on I-15, near Temecula, California. The latter is located inland on a parallel major north-south highway, and about as far north of the border as the checkpoint on I-5. (See app. II, fig. 10, for a map of this sector that shows the location of these checkpoints.) The study reported that when the I-5, San Clemente checkpoint was closed, apprehensions at the I-15 Temecula checkpoint fell sharply—there was a 50 percent decline in 1 month. According to the study, this demonstrated that illegal entrants became aware of the closure and therefore chose the I-5 San Clemente route with no checkpoint, while avoiding the I-15 Temecula route with an operating checkpoint. The Border Patrol told us that this demonstrated the interdependence of various checkpoints operations and that illegal entrants were, in fact, deterred from transiting routes with checkpoints when unmonitored alternatives are available. This study, however, did not address whether the checkpoints completely deter any aliens from entering the country. As additional illustrations of the potential effects of interior checkpoints, Temecula station officials described the following operations that in their view appeared to confirm that illegal aliens had changed their intended routes in order to avoid the checkpoints at Temecula and San Clemente: San Diego sector intelligence analysts determined that illegal alien smugglers were avoiding the permanent Border Patrol interior checkpoints on the highways at San Clemente (I-5) and Temecula (I- 15). Instead, they were taking a circuitous route from the San Diego area to eastern California and western Arizona, and then turning north on secondary highways without checkpoints to make their way to Los Angeles. In response to this intelligence, the Temecula station set up an August 2004 3-day traffic observation operation along I-10 between Los Angeles and Arizona. During the operation, Border Patrol agents stopped 30 suspect vehicles, and apprehended 134 illegal aliens. Border Patrol officials confirmed the earlier intelligence that illegal aliens were utilizing the I-10 route, without checkpoints, to avoid checkpoints on I-5 and I-15. The officials believe that this demonstrated the effectiveness of the permanent I-5 and I-15 interior checkpoints as deterrents that cause illegal entrants to seek out less traveled, unmonitored alternative routes, even if longer in distance and time required to reach major U.S. cities. On May 3, 2004, three vans ran (transited without stopping despite orders to do so) the Otay Mesa port of entry near San Diego, and two vans proceeded north on I-15 (one was stopped near the port of entry). Temecula station officials were alerted to the fleeing vans and were notified that to avoid the checkpoint on I-15, the vans had turned onto a secondary road that roughly paralleled the interstate. Four tactical checkpoints were operating in the area, and the vans were stopped by agents at two of these checkpoints. A total of 48 illegal aliens were arrested. According to Temecula station officials, this incident showed that (1) illegal alien smugglers know that the permanent checkpoints such as the one on I-15 are to be avoided if possible, and (2) tactical checkpoints on secondary roads are valuable and effective for apprehending aliens attempting to circumvent checkpoints on major highways. Temecula station officials described another operation as an example of checkpoint deterrence effectiveness. On the basis of intelligence, Temecula station intelligence analysts concluded that smugglers of illegal aliens had altered their entry routes to avoid the significant Border Patrol presence in the San Diego sector. These altered entry routes included the use of I-40 westbound to enter the greater Los Angeles area; the Border Patrol did not have checkpoints or a constant presence on westbound I-40. In response to this intelligence, the Temecula station conducted a traffic observation operation with multiple marked patrol vehicles on I-40 over a period of 3 days in November 2004, to interdict alien smugglers using the westbound I-40 corridor to circumvent the permanent checkpoints on I-5 and I-15. The I-40 operation was conducted shortly after a Border Patrol I-10 operation with the expectation that smugglers would use I-40 to avoid I-10. The Border Patrol operation found 7 vehicles with 77 illegal aliens. Of these, 60 had entered the country east of the San Diego sector, circumventing the I-5 and I-15 checkpoints. According to Temecula station officials, this confirmed that I-40 is a major smuggling route and that the permanent checkpoints on I-5 and on I-15 serve as deterrents to at least some illegal traffic, as intended. Local law enforcement, business, and community leaders near interior traffic checkpoints in Temecula, California, in the San Diego sector, and Nogales, Arizona, in the Tucson sector, that we interviewed told us that in their view, the checkpoints and the presence of Border Patrol agents were of considerable benefit to their communities. However, in the small community of Tubac, Arizona, we found local criticism of interior traffic checkpoints. Since we did not conduct a comprehensive survey of all communities in the vicinity of all 33 permanent checkpoints in the southwest border states, our findings are limited to the views of the local citizens and law enforcement officials with whom we met in the communities we visited, as well as statements by the Border Patrol with regard to their relationships with local communities near checkpoints. We did not confirm the views expressed by these citizens and officials, as little data were available relating directly to their statements. Officials representing the city of Temecula, California, the Temecula Police Department, and the Chamber of Commerce, for example, all said that the nearby I-15 traffic checkpoint and Border Patrol presence benefit their community. The checkpoint has the second greatest average daily volume of vehicular traffic among the Border Patrol’s checkpoints, with about 122,000 vehicles passing through the checkpoint location daily. City and police officials said that having the checkpoint in operation means that illegal aliens and drug smugglers are intercepted and taken off the streets, reducing crime and vandalism. One city official also said that traffic problems with the checkpoint have been minimal, and that the city has received very few calls complaining about the checkpoint and what amount to minimal delays when the checkpoint is operating and checking traffic. The official said that the majority of the calls that the city received were before September 11, 2001, and very few calls had been received since then. The President of the Temecula Chamber of Commerce conducted an informal survey of member businesses, and only one business mentioned that some employees said that the checkpoint operations occasionally delayed their commute to or from work. Overall, the Chamber President concluded that the checkpoint is not a concern to the community. The Santa Cruz County Attorney from Nogales, Arizona, told us that the Border Patrol and its checkpoints were among the best protections for fighting illegal alien traffic and local crime, with a side benefit of detecting drunk drivers on their way back from Mexico. According to this official, the I-19 checkpoint between Nogales and Tucson was a major benefit to the community because it was saving lives, apprehending illegal aliens, and arresting drug smugglers. The official also stated that, in her opinion, the checkpoints are effective in apprehending drug violators out of proportion to the resources deployed at the checkpoints and voiced the view that permanent checkpoints were better than tactical ones. In contrast to the generally positive view of the benefits resulting from the Border Patrol checkpoints from others that we interviewed, the president of a local civic association from Tubac, Arizona (population 949), located between Nogales and Tucson near the I-19 nonpermanent Tucson sector checkpoint at KP 42, told us that he believed the checkpoint was disruptive to the community and was not effective because illegal aliens were circumventing the checkpoint and passing through the community. He said that the checkpoint had affected home sales and housing values, and that most local residents were strongly opposed to having a permanent checkpoint built near them on I-19, because of fears about the impact on traffic congestion and overall quality of life. We were also told by congressional staff that the overwhelming majority present at April and July 2005 community meetings in Tubac had voiced opposition to the possibility of a permanent checkpoint on I-19 near Tubac. The Border Patrol Handbook states that checkpoint operations should be suspended if there is “too much traffic congestion” and does not further define this. However, some sector checkpoints have more precise guidance pertaining to a specific distance or length of time traffic will be permitted to back up. Agents said they know from experience the amount of wait time that is created by how far back from the checkpoint the lines of vehicles extend. The maximum delays that we observed appeared not to exceed the restrictions defined by the checkpoint guidance prepared by certain sectors. This was the case, for example, at I-5 near San Clemente, which has the single greatest daily volume of traffic in the country (about 144,000 vehicles per day) among interior Border Patrol checkpoints, and at I-15 near Temecula, the next highest, with about 122,000 vehicles daily. At the times we visited, at both locations, we observed that the agents temporarily stopped checkpoint inspections when estimated delays exceeded guidelines. Traffic was then “flushed” and permitted to flow through until there was no line of waiting vehicles. Screening operations were then resumed. We also observed during our visit to the San Clemente checkpoint, traffic flow in the opposite southerly direction, where there is no checkpoint, sometimes was heavier and slower than on the side with the ongoing checkpoint operation. Moreover, of the more than 400 statewide cameras maintained by the California Department of Transportation to monitor traffic, none are at either the Temecula or San Clemente checkpoints, according to the department. In response to our questions, the department stated that it had not received reports in recent years on congestion or related problems at either the I-5 or I-15 checkpoints, and it had not conducted studies of the checkpoints. We contacted several other organizations that monitor traffic congestion as part of their work, such as the Automobile Club of Southern California, and the California Highway Patrol, to ask if they had received complaints about the San Clemente or Temecula checkpoints in California, or had observed actual traffic backups at these checkpoints. We also asked the American Trucking Associations if it had received complaints from commercial shippers about checkpoints in the southwestern states. None of these organizations cited complaints in recent years about these checkpoints. In addition, an official of an organization that promotes economic development in Laredo, Texas, and who is active in monitoring the impact on traffic of the checkpoint on I-35 north of Laredo, stated that traffic delays were minimal even at the I-35 checkpoint, and that anyone living on or near the border is familiar with the checkpoints as a fact of life. He believed that commercial truckers build in potential travel delays, which are longer for commercial vehicles than for cars, into their cost of doing business and transit times. He noted that even during rush hours, he believed that trucks did not wait more than an average of about 20 minutes maximum, based on what he had observed in recent years. Cars are delayed considerably less, averaging perhaps a 5-minute delay in rush hour, he stated. We observed this checkpoint, and delays appeared not to exceed 5 minutes at the time we visited, based on the time that it took for cars at the back of the line to transit through the checkpoint. At the tactical checkpoint on I-19 between Nogales and Tucson, Arizona, we saw minor traffic backups of not more than about a half dozen vehicles at any time over the course of about 1 hour. We were told that this was typical for this time of year; delays did not last more than 2 or 3 minutes for vehicles transiting the checkpoint during our site visit. However, the Border Patrol also told us that when truck traffic is particularly heavy during the spring harvest season, pulling trucks over to the side of the road to inspect them can create backups that cause safety problems and delays for the truck drivers. We also observed traffic patterns at permanent checkpoints on I-35 north of Laredo and on U.S. highway 281 at Falfurrias, Texas, both major highways, and at a permanent checkpoint at Hebbronville, Texas, on a secondary road between Falfurrias and Laredo. Although traffic backups occurred on occasion at these locations, we were told that they generally did not last more than a few minutes, as additional agents or lanes are added to reduce delays. During our visit, Border Patrol agents appeared to be monitoring the amount of traffic waiting in line, which caused less than about 5 minutes’ wait time, and usually less. Agents told us that if traffic backs up, they add extra agents to the inspection lanes, and may open additional lanes as well. At some holiday periods, however, we were told delays can reach 20 to 30 minutes. The volume of traffic at the Texas checkpoints we observed was much lower than that on I-5 and I-15 in California, permitting what amounts to a near 100 percent check of transiting vehicles, according to the Border Patrol. This is feasible when average daily traffic volume is about 13,700 vehicles, as is the case at the Laredo, Texas, checkpoint, compared with more than 120,000 at I-15, near Temecula, California, or over 140,000 at I-5, near San Clemente, California. Border Patrol officials told us that costs of operating the permanent and tactical checkpoints are not routinely or systematically maintained or reported because checkpoints are integral and interdependent parts of the multilayered enforcement strategy. As such, permanent and tactical checkpoints are supported with facilities, personnel, equipment, and canines, for example, and by their associated stations, which in turn are supported by the sector as a whole. Tactical checkpoints in particular are often set up specifically to support the permanent ones, often on a changing daily basis. Agent manpower levels may also vary at both the permanent and the tactical checkpoints, depending on how the Border Patrol decides on a given day to best allocate personnel resources, in response to traffic volume, intelligence on illegal entrant routes, and other factors, such as weather. For example, the permanent checkpoint at I-15 Temecula is supported by up to eight tactical checkpoints that are set up as needed, based on intelligence data on illegal alien traffic on the sector’s secondary roads. The costs of one tactical checkpoint versus another are not readily separable, except perhaps the personnel costs, and even then, those could vary over a period of hours, according to Border Patrol officials. A question that the Border Patrol officials asked and which has no easy or standard answer was “If an agent must transport arrested aliens or smugglers to a station headquarters, should his/her salary be counted as part of the roadside checkpoint, or the station headquarters support?” Even considering these obstacles to checkpoint cost comparisons, we asked Border Patrol officials whether they could supply us with individual checkpoint operating costs to include facilities, equipment, personnel, and any other costs. Border Patrol officials queried the sectors and stations at the locations we visited and asked whether cost data could be assembled. The sectors and stations responded with what cost data they could locate, but it was not possible to obtain similar data from each location, and the data provided would not be reliable enough to present any meaningful statistics concerning costs of operating interior traffic checkpoints. In reviewing Border Patrol reports, and in discussions with Border Patrol officials, we found that the Border Patrol has not systematically evaluated the effectiveness of interior checkpoint operations. The Border Patrol does gather and report traditional law enforcement data, including the number of apprehensions, historical apprehension trends, and weight and type of contraband seized, but could not provide us with reports or analyses that assessed the performance of one sector compared to another, or of interior checkpoints compared with line operations. Thus, the Border Patrol does not have analyses based on inputs (costs), such as agent work years, divided into outputs, such as apprehensions or contraband seized, that could help measure effectiveness or productivity and that could therefore also be used in making decisions about how best to allocate resources. The Border Patrol stated that it has not evaluated the effectiveness of its interior checkpoints largely because checkpoints are part of a multilayered enforcement strategy and cannot be easily separated for evaluation purposes. Furthermore, officials stated that because such outcomes as deterrence are difficult to measure (i.e., estimating how many crimes or illegal entries were deterred before they happened), the Border Patrol has chosen to rely on the types of data cited above to gauge effectiveness. A key component to assessing unit operations is the development of performance measures. We have previously reported on the need for federal agencies to develop performance measures of their programs and to use such measures to improve their performance, as well as to be in compliance with the Government Performance and Results Act of 1993 (GPRA). As we noted, under the act, “every major federal agency must now ask itself some basic questions: What is our mission? What are our goals and how will we achieve them? How can we measure our performance? How will we use that information to make improvements? GPRA forces a shift in the focus of federal agencies—away from such traditional concerns as staffing and activity levels and toward a single overriding issue: results. GPRA requires agencies to set goals, measure performance, and report on their accomplishments.” Organizations use performance measures to help demonstrate the level of progress in achieving results, to inform decision makers, and to hold managers accountable. To better articulate a results orientation, organizations create a set of performance goals and measures that address important dimensions of program performance. Establishing and using performance measures for checkpoint operations and other strategy components would allow the Border Patrol to help assess the comparative success of each checkpoint in addressing program goals as well as checkpoints generally in comparison with line and patrol operations. A comparison of the effectiveness of each sector, using performance measures, would permit the Border Patrol to more meaningfully assess the success of its overall strategy than does a count of total apprehensions or contraband seizures. Without knowing how much effort produced an outcome—in this case, apprehensions or contraband seizures—it is difficult to know if one sector or region is performing better than another (on a per input basis). With such knowledge, more effective management strategies can be devised, if needed, to better allocate agency resources, in conjunction with other data and information. We acknowledge that developing performance measures applied to all checkpoints can be challenging for the reasons stated by Border Patrol officials. Nevertheless, it is important that the Border Patrol develop performance measures to gauge success in meeting strategic goals and that these measures go beyond the traditional output data it currently uses to indicate the effectiveness of law enforcement efforts. Although the Border Patrol told us that the legislative restrictions on funding for construction of checkpoints in the Tucson sector, combined with the requirement to relocate checkpoints on a 7- or 14-day schedule, had reduced their effectiveness, it did not have a data-based analysis to support these statements. It did have data, by sector, on apprehensions of illegal entrants at interior checkpoints and for line watch/line patrol, as well as for work hours charged at interior checkpoints and line watch/line patrol. (Agent work hour data have not been maintained by the Border Patrol for tactical checkpoints versus permanent ones and were therefore not available.) To test the feasibility of developing additional measures of performance that would address these concerns, we used Border Patrol data to measure apprehensions per agent work year and cost of apprehensions per agent work year. Such measures might help to determine if the available data support the Border Patrol’s statements on the impact of the legislative restrictions on the Tucson sector’s interior checkpoints effectiveness. In applying the apprehension per agent work year measure, we compared the performance of the Tucson sector interior checkpoints over the period of fiscal years 2001-2004 with those of the interior checkpoints in the three other sectors we visited. We limited the comparison to these four sectors because a considerable amount of the work hour data had to be collected by the Border Patrol through data calls, which placed a time burden on those collecting the data for us. We examined the data starting with fiscal year 2001, the last year for which the impact of the terror attacks of September 11 were largely not felt on illegal immigration, through fiscal year 2004, the last year for which data were available at the time of this report. Throughout this period as well, no funding had been permitted for construction of checkpoints in the Tucson sector. Our analysis of Border Patrol data suggest that, as measured in apprehensions per agent work year, the restrictions in the Tucson sector may have had a negative impact on the performance of its interior checkpoints, starting at about the time the sector implemented direction from congressional staff to relocate checkpoints every 7 days, in comparison with the three other sectors we visited, where no comparable decline in effectiveness occurred during the same time period. According to the Border Patrol, its records show that it began relocating the Tucson sector’s checkpoints every 7 days in June 2002, which meant closing some of them, as explained previously. Figure 9 shows the apprehensions per agent work year at interior checkpoints for each of the four sectors we visited, for fiscal years 2001- 2004, and the apprehensions per agent work year for line patrol/line watch along the border. Figure 9 shows that apprehensions per agent work year at the Tucson sector interior checkpoints fell 48 percent from fiscal year 2001 to fiscal year 2002, when the 7-day relocation procedures were put into effect, with about 4 months remaining in the fiscal year. This was followed by a 77 percent decrease from fiscal year 2002 to fiscal year 2003, when the 7-day relocation requirement was in effect for the entire fiscal year. The overall decrease from fiscal year 2001 to fiscal year 2003 was about 88 percent, in the Tucson sector. Apprehensions per agent work year rose from fiscal year 2003 to fiscal year 2004, but the 2004 level was 77 percent below the fiscal year 2001 level. In contrast to these performance measures for the Tucson sector interior checkpoints, apprehensions per agent work year for same period at the interior checkpoints in the three other southwest sectors (San Diego, California; Laredo, Texas; and McAllen, Texas) we visited—that were not subject to the funding restrictions or the relocation requirements—either stayed at about the same level over this period or increased somewhat. During fiscal year 2001 to 2002, when Tucson apprehensions per agent work year fell 48 percent, apprehensions per agent work year fell less than 2 percent in the San Diego sector, decreased about 19 percent in the Laredo sector, and decreased about 12 percent in the McAllen sector. The Border Patrol attributed the drop in apprehensions in these and other sectors in this period to a general decrease in illegal border crossings after September 11 but attributed the greater decline in the Tucson sector to relocating the Tucson checkpoints on a regular 7-day basis, starting in June 2002. Border Patrol officials told us that they were not aware of any other changes or factors that would have caused the reduction in Tucson compared with other sectors other than the combination of the funding restrictions and the 7-day relocation requirement. Moreover, apprehensions per agent work year at interior checkpoints in the Tucson sector fell by about 77 percent from fiscal year 2002 to fiscal year 2003, while they either remained about the same or increased (more than doubling in San Diego) in that period in the other three sectors. In the San Diego sector, interior checkpoint apprehensions per agent year increased about 60 percent from 2003 to 2004 and were almost four times the 2002 level (versus Tucson, where the 2004 level was 55 percent below the 2002 level). In the McAllen and Laredo sectors, there was almost no difference in checkpoint apprehension rates between 2003 and 2004. The Border Patrol believes that the differences between the Tucson sector and others with regard to interior checkpoint performance are in large part the result of the requirement to relocate checkpoints every 7 days at that time. Border Patrol officials stated that the smugglers can easily determine when the tactical or nonpermanent checkpoints in any location must relocate or close and are therefore able to evade them by waiting until they move or close, and a potential vulnerability in border security has been created. It is important to note that we did not evaluate all the factors that might have contributed to the differing performance results between Tucson interior checkpoints and those in the other three sectors. There could have been other factors beyond the restrictions on construction of checkpoints and the requirement to relocate every 7 days that affected checkpoint performance, such as the unknown number of persons attempting entry into a sector, varying topographic conditions and road networks, and the fees charged by smugglers to smuggle illegal immigrants into the United States. Nevertheless, while there may have been other factors that affected the performance of interior checkpoints in the four sectors, the data in figure 9 should not be overlooked when considering the results or impacts of policy or management directives. In the second performance measure, we converted the apprehensions per agent work year into costs of apprehensions per work year, or cost per apprehension. We then compared interior checkpoints cost per apprehension (per work year) with costs per apprehension (per work year) for line watch and line patrol operations. We were unable to develop costs per apprehension at permanent versus tactical checkpoints because individual checkpoint cost data are not maintained by the Border Patrol. In addition, this measure is based on agent labor costs at interior checkpoints and line watch/line patrol and does not include overhead costs, such as those for equipment, training, buildings, canines, and so forth. Converting the fiscal year 2004 apprehension data into cost per apprehension (per work year), apprehensions in the San Diego sector at the border (line watch/line patrol) cost $384 per apprehension, and about $277 per apprehension at the interior checkpoints (both permanent and tactical). In the Tucson sector, for the same fiscal year, border apprehensions cost $126 each per work year, and interior checkpoint apprehensions cost $445 each. These ranges of cost per apprehension (per work year) are not, however, necessarily reflective of agents at one checkpoint or in one sector working harder or more effectively than those in another sector and must be considered in the context of the Border Patrol’s integrated, multilayered strategy, which seeks to deter illegal entrants through the perceived risk of apprehension. Thus, a permanent checkpoint with a substantial infrastructure may have many agents, such as at I-5 near San Clemente (with about 100 agents assigned to the location) but may have comparatively few apprehensions—because it has successfully deterred potential illegal entrants. In Temecula, California, agents are required to monitor alternative routes through the hills around the I-15 permanent checkpoint. Again, many agents may be required, but few apprehensions may occur, if illegal entrants are deterred to alternative routes, such as the circuitous I-10 route previously described. In contrast, a sector with many illegal entrants, such as Tucson, may effect many apprehensions because of the volume of illegal entrants, seemingly showing border cost per apprehension to be much lower than in San Diego. Yet the reality is that the long-term legacy INS and now CBP strategy of closing off the easiest routes (in San Diego, El Paso, and McAllen), has led to the high volume in the Tucson sector. Therefore, cost per apprehension or any other single performance measure cannot be used without taking into account the overall strategy. While a performance measure such as cost per apprehension can provide some information on cost-effectiveness, several additional caveats exist. First, regarding the output measured in the denominator (i.e., the number of apprehensions per agent work year, such as 191 for San Diego in fiscal year 2004), some apprehensions may be considered more important to the agency than others. For instance, apprehending a drug smuggler or a terrorist might be considered more important than apprehending an illegal alien job seeker. Second, regarding the cost of inputs measured in the numerator (e.g., the $53,000 annual average agent nationwide salary), numerous cost measures can exist. The most easily applied is often the variable cost of labor that is used above and which may require estimation. Other input costs may exist but may be difficult to assign to a given apprehension, since not only are indirect overhead costs involved (e.g., training, equipment, infrastructure, canines), but also such costs as the differing salaries of multiple agents, if more than one was involved in the apprehension; the time used up by each different agent; and the processing costs, which can vary by suspect, depending on whether the person is already in a national database or cannot be identified. The two performance measures we developed would not alone fully assess or explain relative success among sectors, and in developing performance measures for checkpoints, a number of factors would need to be considered. For example, in comparing the apprehensions per agent work year and cost per apprehension for the adjacent McAllen and Laredo sectors, considerable differences appear, with McAllen checkpoints apprehending far more illegal aliens per agent work year than Laredo. Converted into cost per apprehension, these data show that for fiscal year 2004, in the Laredo sector, the cost per apprehension for line watch/line patrol was $411, while the cost per apprehension at checkpoints was $930 each. For McAllen, the cost per apprehension at line/patrol was $609, while the cost at the checkpoints was $195 per apprehension. Taken alone, and without additional information about conditions in these sectors, these costs per apprehension are not necessarily a useful guide to management decisions about resource allocation. As Border Patrol officials told us, several factors are believed to contribute to the differences in apprehension patterns between McAllen and Laredo sectors. These include the topography, availability of egress routes, staff deployment, and varying expedited removal programs. Further, the McAllen sector includes two major Mexican cities adjacent to its border with a combined population of about 2 million people and an infrastructure that facilitates potential illegal entrants. These factors provide context to the analysis and underscore the importance of the Border Patrol developing a range of performance measures that can adequately account for differences among sectors and provide decision makers with reliable indicators of success. The usefulness of these measures notwithstanding, other performance measures and relevant factors would also be useful in assessing the effectiveness of checkpoints relative to other elements of the multilayered strategy. Some available information, beyond apprehensions and contraband seized, could help the Border Patrol make more informed decisions about where its operations are most effective and how best to allocate resources to make needed improvements. For example, the Border Patrol could consider the cost of smuggling charged to illegal immigrants as a measure of its overall effectiveness. Additionally, the Border Patrol could consider the number of apprehensions or contraband seizures per the number of vehicles sent to secondary inspection as a measure of effectiveness. There are likely other measures that could use existing or easily gathered data to help measure effectiveness across the range of Border Patrol line watch, line patrol, and interior traffic checkpoint activities. These kinds of performance measures can aid in making resource allocation decisions, provided again that such decisions are made with reasonable knowledge of other conditions present in a given sector or region. It is unlikely that either the first two lines of border defense, line watch and line patrol, or the interior traffic checkpoints, another layer of defense, will ever be 100 percent effective in catching all smugglers or aliens illegally entering the United States. This is the case given the 1,950 mile southwest border, the number of personnel and the cost required to cover all of this area, the continuing sophistication of smugglers using modern technology to observe and evade the Border Patrol’s enforcement efforts, and the differences in wages, job opportunities, and perceived life opportunities between Mexico and the United States. However, the Border Patrol’s interior traffic checkpoints—both permanent and tactical—have distinct functions in its integrated, multilayered strategy intended to detect and deter potential terrorists, illegal immigration, and contraband smuggling into the United States. While the permanent checkpoints are the anchors of this part of the strategy, the tactical checkpoints reinforce the permanent ones at those locations where smugglers, illegal aliens, or terrorists can use secondary roads to avoid the permanent checkpoints, and when intelligence can help direct redeployment of tactical checkpoints to counter new infiltration routes. Working in tandem, the interior checkpoints combine the high-technology capabilities and detention, processing, and inspection facilities of the permanent checkpoints with the element of flexibility that tactical checkpoints can offer. Trying to measure the effectiveness of its border enforcement deterrence strategy has been a long-standing challenge for legacy INS and now CBP and the Border Patrol. As many illegal aliens and contraband smugglers continue to evade the border defenses, the need to measure effectiveness and allocate scarce resources grows in significance. In its Performance and Annual Report, CBP uses traditional law enforcement effectiveness measures, such as numbers of apprehensions and contraband seizures to describe the Border Patrol’s performance. While these measures serve as worthwhile indicators, the annual reports do not compare the effectiveness of line watch and line patrol with the effectiveness of interior traffic checkpoints. These traditional measures also do not delineate the performance of permanent, tactical, and nonpermanent checkpoints. In contrast, performance measures that take inputs and outputs into account, such as agent work years divided by apprehensions, provide a basis for helping make decisions about how best to allocate agency resources, in conjunction with other information and data. Such measures can also help identify trends that might otherwise not be apparent using traditional data, as shown by our analysis of the data on performance of the Tucson sector nonpermanent interior checkpoints compared with the performance of other sectors. Apprehension data alone would not have shown the trend of the decrease in apprehensions per agent work year that occurred at the Tucson sector checkpoints, starting at about the same time the 7-day relocation requirement went into effect, while no comparable decrease occurred in the three other sectors without the requirement. Moreover, apprehensions per agent work year, and the cost per apprehension, along with information on many other relevant factors, could provide useful trend information on the relative cost efficiency of these components of the multilayered enforcement strategy. Other measures of performance and effectiveness might also be developed using existing or easily gathered information to assess checkpoint operations and performance, as well as other border enforcement activities. This information could also be useful to the Congress as it considers ways to improve the effectiveness of checkpoints and border security efforts. To better gauge the effects of border control efforts, we recommend that the Commissioner of Customs and Border Protection develop additional performance measures for the Border Patrol for the productivity and effectiveness of interior checkpoints, such as apprehensions per agent work year and cost per apprehension, and include in CBP’s Performance and Annual Report data and analysis provided by the additional performance measures on the performance of interior checkpoints and what might be done to improve their effectiveness. We requested comments on a draft of this report from the Secretary of Homeland Security. In its response, DHS said the report is factually correct, agreed with our recommendations, and stated that CBP is taking steps to implement them. With regard to our first recommendation, that the Commissioner of Customs and Border Protection develop performance measures for the Border Patrol in addition to its traditional ones, for the productivity and effectiveness of interior checkpoints, DHS stated that CBP is in the process of developing such measures for the Border Patrol for fiscal year 2006 and that one or more of the performance measures will gauge the effectiveness of checkpoints. DHS stated that CBP will consider our suggestions when developing these measures. With regard to our second recommendation, that CBP include in its Performance and Annual Report data and analysis provided by the additional performance measures on the performance of interior checkpoints, and what might be done to improve their effectiveness, DHS stated that once the performance measures for fiscal year 2006 for the Border Patrol are implemented and the data are tracked, CBP will publish the information in its Performance and Annual Report. DHS’s comments are reprinted in appendix VI. DHS also offered technical comments, which we considered and incorporated where appropriate. We are sending copies of this report to the Secretary of the Department of Homeland Security and interested congressional committees. We will also make copies available to others upon request. In addition, the report will be available at no charge on GAO’s Web site at http://www.gao.gov. If you or your staff have any questions about this report, please contact me at (202) 512-8777 or StanaR@gao.gov. Contact points for our Office of Congressional Relations and Public Affairs may be found on the last page of this report. GAO staff who made key contributions to this report are listed in appendix VII. To address our objectives, we examined and analyzed Border Patrol documents, reports, manuals, and guidance concerning border strategy and checkpoint operations. We interviewed cognizant Border Patrol officials at Washington, D.C. headquarters, officials in four sector offices, and personnel at selected permanent and tactical checkpoints. We visited sector headquarters, stations, and interior traffic checkpoints in four Border Patrol sectors—San Diego, California and Tucson, Arizona, and two in southeastern Texas, Laredo and McAllen. In total, we visited three sector headquarter offices, seven stations, five permanent checkpoints, and three tactical checkpoints. Sector offices and interior checkpoints we visited had one or more of the following characteristics: offices that oversee permanent or tactical checkpoints, or both, to obtain information about both types, permanent, nonpermanent, and tactical checkpoints with high, medium or low vehicular traffic volume, permanent, nonpermanent, and tactical checkpoints with high, medium or low estimated smuggling volume (either aliens or contraband, or both), and checkpoints that varied in terrain, with some situated with little peripheral area to evade the checkpoint and others situated so that patrols must be set up to prevent end runs. We visited and observed operations at the following Border Patrol sectors, which were selected to provide a range in type and size of operation: Border Patrol stations and checkpoints in the Tucson, Arizona, sector where only nonpermanent checkpoints are permitted under current law, and because that sector has the most annual apprehensions of illegal immigrants. Also, we wanted to compare the operations of the Tucson sector interior checkpoints with the operations of tactical and permanent ones elsewhere. Permanent and tactical checkpoints in the San Diego, California, sector because it contains two permanent ones with high volume—Temecula and San Clemente—and two requesters asked that these be included in a broader study of the effectiveness of all interior traffic checkpoints. Permanent checkpoints in Texas at Falfurrias and Hebbronville, and on I-35, north of Laredo, as well as Border Patrol stations in Falfurrias and Hebbronville. The former is in the McAllen sector, while the latter is in the Laredo sector. Ports of entry at San Diego, California; Douglas, Arizona; and Laredo, Texas. We did so in order to better understand the differences between the operations of these ports of entry at the international border and the operations of the interior traffic checkpoints. Via helicopter, we observed the terrain and Border Patrol activities along a 60-mile section of the international border, from San Diego inland and along approximately 200 miles of the border in the Tucson sector, from Ajo to Douglas, Arizona. The four sectors we visited were selected to provide a substantial range in the size and types of interior checkpoint operations; estimated volume of illegal annual immigration; volume of vehicular traffic transiting checkpoints; topography and density of road networks; presence or absence of large urban areas on or near the border, both on the U.S. and Mexican sides; and types of checkpoints (permanent, nonpermanent, and tactical). As we were told by the Border Patrol in deciding which sectors and checkpoints to visit, and as we found during our site visits, these four sectors contained a wide variety of operating conditions. For example, the San Diego sector’s permanent checkpoint near San Clemente on I-5 has the highest volume of average daily vehicle traffic among the Border Patrol’s 33 permanent checkpoints on the southwest border, while those north of Laredo, Texas, and at Falfurrias, Texas, average daily traffic volume about one-tenth that amount. Some of the tactical checkpoints we visited have average daily traffic volume that is only about one-hundredth that of San Clemente/I-5—that is, 1,500 vehicles or less daily, according to the Border Patrol and based on our observations during site visits. Similarly, there were substantial variations in the estimated numbers of illegal immigrants entering these sectors over the last several years, and wide differences in topography, with some being comparatively mountainous and others being comparatively flat. The Laredo and McAllen sectors have the Rio Grande as a natural barrier during the winter months to illegal immigration, while the Tucson sector has a flat desert at the border that is easily crossed. Some sectors have permanent checkpoints, such as at Temecula, California, that must be supplemented with tactical checkpoints, because of substantial secondary road networks around the permanent checkpoint. Others, such as McAllen, have no alternative secondary roads available to evade the permanent checkpoints on the limited north-south highways. Some sectors, such as San Diego and Laredo, have large U.S. and Mexican urban areas on or very near the international border, while others, such as Tucson, have only a few much smaller cities on either side at the border. In choosing these sectors, which are located in three of the four southwest border states (California, Arizona and Texas, but not New Mexico) we sought and found a wide range of conditions that appear to reasonably represent the range of operating conditions faced by the Border Patrol across the Southwest. However, it is also the case that we were unable to observe all operating conditions at all times and that the conditions we describe are therefore based on available documentation and observations at our site visits only. We also interviewed selected officials in communities near some of the interior checkpoints, including local law enforcement and community officials, selected community leaders, citizens, and owners of local businesses. These included the communities of Temecula, California; Nogales, Arizona; Laredo, Texas, and the small town of Tubac, between Nogales and Tucson, Arizona. Because these places and persons were selected using a nonprobabilistic method, the results from our site visits cannot be generalized to other locations, checkpoints, local officials, or citizens. We contacted organizations that could be expected to monitor traffic congestion as part of their work, including the Automobile Club of Southern California, the American Trucking Associations, the California Department of Transportation, and the California Highway Patrol. We asked these organizations for reports, studies, or information on traffic congestion at selected interior traffic checkpoints we had visited, in particular those with high daily vehicle volume. To assess the reliability of the Border Patrol’s data on apprehensions, contraband seizures, and work hours, we talked with agency officials at both Washington, D.C., headquarters and some Border Patrol stations in the field about data quality control procedures, including methods by which data are checked and reviewed internally for accuracy and consistency. We also obtained and reviewed relevant documentation. We determined the data on apprehensions, contraband seizures, and work hours were sufficiently reliable for the purposes of this report. However, we agreed with Border Patrol officials that the data on costs of checkpoints were not sufficiently reliable to be used. To determine whether available Border Patrol data could be used to measure the performance of interior checkpoints compared with the performance of operations on the border (line patrol and line watch), both within and among Border Patrol sectors, we developed two measures of performance—apprehensions per agent work year and cost of apprehensions per agent work year. We chose to do this because the Border Patrol uses only traditional law enforcement measures to report on its performance, including apprehensions and amount and type of contraband seized. These are not assessed relative to the inputs (agent labor, overhead costs) that went into achieving them and therefore do not provide a guide on how to better allocate agency resources. To develop our first performance measure, apprehensions per agent work year, we obtained data from the Border Patrol for each of the four sectors we visited on the total number of agent work hours recorded as charged by agents who work at interior checkpoint operations, and for line watch and line patrol. (Line watch and line patrol operate very closely together on the border, and data are not recorded separately for them by the Border Patrol.) We were unable to perform an apprehensions per agent work year analysis for permanent or tactical checkpoints because data on agent hours charged to individual checkpoints are not recorded. That is, while work records are kept for hours charged by agents at interior checkpoints, the records do not distinguish between hours charged at permanent checkpoints versus those charged to tactical checkpoints in the same sector. Using the data charged to interior checkpoints and line watch/line patrol for each sector, we then divided these total hours by 2,080, which is the total number of hours in a standard work year of 52 weeks, and 40 work hours per week. (The Border Patrol work year is the same as that of the rest of the U.S. government.) The total agent work hours at checkpoints in a given sector, divided by 2,080, produced a data point that we called agent work years. Thus, if 2,080,000 hours were charged, the work year total would have been 1,000 work years—2,080,000 divided by 2,080. To calculate what we term apprehensions per agent work, we then took the data we had obtained on the number of apprehensions that occurred at interior checkpoints in each sector in a given fiscal year and divided that number by the agent work year calculation. For example, if 10,000 apprehensions occurred at interior checkpoints in a sector, and 2,000 agent work years had been recorded as having been worked at those checkpoints, the apprehensions per agent work year were 5 (10,000 apprehensions divided by 2,000 work years). Of course, this did not include the work of support personnel that contribute indirectly to the outcome of apprehensions. Our second measure was cost per apprehension, with apprehension actually being apprehension per work year, to control for the known input of agent work years. We chose this measure because a question that is frequently, if not almost universally, asked about government programs, is, “What is known about their cost effectiveness?” One potential measure of such cost effectiveness for the Border Patrol would be how much did it cost to apprehend a single person in one sector, compared with other sectors? While this measure and others should not be taken in isolation as further guides to management decisions, knowledge of the basic costs of an agency’s key outcomes (such as apprehensions of illegal entrants) per unit of input (agent labor costs) can be part of the basis for improved allocation of resources. Of course, it would be even better if the full costs of all the inputs were known, such as infrastructure overhead, but these were not available. Therefore, we used data that were available as a method of illustrating how cost effectiveness measures could be more fully developed by the Border Patrol. To calculate cost per apprehension per agent work year, we divided the outputs by the inputs—in this case, the data on apprehensions per work year (e.g., 521 in Tucson in fiscal year 2001) divided by the average cost of an agent work year in fiscal year 2004, which the Border Patrol stated was $53,000, or the nationwide average for the GS-11, step 2, rank. This was described as the national average for Border Patrol agents; of course, it is an average for all agents, and does not reflect variations in cost of living adjustments, or for the true wider range of all Border Patrol salaries. We used the $53,000 average work year cost for all calculations for the period covering fiscal years 2001-2004 and did not adjust the work year cost for inflation. Our goal was again to show what the approximate cost per apprehension had been and how this measure could serve as a resource allocation tool, along with other information and data. We conducted our work from September 2004 to May 2005 in accordance with generally accepted government auditing standards. The San Diego sector’s area of responsibility includes all of San Diego County and substantial portions of Orange and Riverside counties in California, covering more than 7,000 square miles and 60 miles of international border with Mexico. The San Diego sector encompasses coastal beaches and expansive mesas to coastal and inland mountains, rugged canyons, and high desert. Over half of the border in this sector consists of mountains, but there are also lesser amounts of rolling brushland, urban hilly terrain, canyons, farmland, flat desert, and flat urban terrain. Directly to the south of San Diego lie the Mexican cities of Tijuana and Tecate, Baja California—with a combined population of more than 2 million. For decades, this area was the preferred corridor for illegal immigration because of the highly populated neighborhoods north and south of the border. At the time of our September and December 2004 visits, the sector was headed by a chief patrol agent, had seven Border Patrol stations, and 1,634 agents on duty. The sector used four-wheel-drive vehicles, police sedans, and vans to patrol between two parallel fences that were constructed along the border, stretching about 16 miles inland from the Pacific Ocean. In addition, the sector uses all-terrain vehicles (ATVs), helicopters, mountain bikes, and horses to patrol border areas. Seismic sensors are also used to identify where smugglers and illegal aliens are attempting to cross the border between the official ports of entry. The sector has 4 permanent interior traffic checkpoints and up to 11 tactical checkpoints, which are operated on an as-needed basis (see fig. 10). The two busiest permanent checkpoints in the sector are the ones located (1) on northbound I-5, south of San Clemente, about 68 miles from the border, and (2) on northbound I-15, near Temecula, also located about 68 miles from the border. Most of the tactical checkpoints in the San Diego sector are operated by the Temecula station, which can field up to 8 tactical checkpoints located on a network of secondary state highways leading roughly northwest from the eastern San Diego area toward Los Angeles, and paralleling or intersecting the major I-15 interstate highway. According to Border Patrol officials, secondary roads make it possible for smugglers and illegal aliens to try to circumvent the I-15 Temecula checkpoint by taking side roads, unlike the San Clemente I-5 checkpoint, which has no surrounding secondary roads. Figure 10 shows the approximate location of the permanent checkpoints, on I-5 (San Clemente) and on I-15 (Temecula), as well as some of the approximate locations used for tactical checkpoints, not all of which operate simultaneously. De Luz Rd. We observed that the operations and physical layout of the two permanent checkpoints at San Clemente and Temecula were largely similar, and although the local geography differs somewhat, both checkpoints are situated at locations with high surrounding hills or other barriers (e.g., the ocean at the I-5 checkpoint), making it difficult to simply drive around the checkpoints. The I-5 checkpoint south of San Clemente has four traffic lanes, and Border Patrol agents stand between the lanes to screen traffic (see fig. 11). Trucks pass through the adjoining weigh station, where they too are screened. The I-15 checkpoint near Temecula is similar to the one south of San Clemente, in terms of the Border Patrol agents having to monitor multiple lanes of traffic on a very busy highway. A major difference is that secondary roads south of the checkpoint offer alternative routes for persons to try to evade the I-15 Temecula checkpoint. According to Border Patrol officials, it is difficult for smugglers and illegal aliens to avoid the San Clemente I-5 traffic checkpoint because it is located in a physically constricted area between high hills on the right (facing north) and the ocean on the left, with no readily accessible side roads for miles prior to the checkpoint, because the Marine Corps’ Camp Pendleton borders it on the east. To circumvent the checkpoint, smugglers and illegal aliens must either go through a state park, where there are state park police, or through the hilly terrain of Camp Pendleton, where there are military police, according to the Border Patrol officials. Vehicles are observable for at least a mile south from cameras at the checkpoint, so that those attempting to improperly enter Camp Pendleton would be visible to the Border Patrol. Figure 12 shows an aerial photo of the I-5 checkpoint, with the hills in Camp Pendleton on the side of the checkpoint area to the upper right, and the ocean to the lower left of the checkpoint, making evasions of the checkpoint difficult. As of November 2004, the San Clemente station was staffed with a patrol- agent-in-charge and approximately 100 Border Patrol agents. The Temecula station was also staffed by a patrol-agent-in-charge and had approximately 127 agents. During our visit to the I-5 checkpoint, we observed agents performing traffic checks (i.e., screening vehicles) by staffing positions on the highway. We observed two agents standing between the lanes of the northbound I-5 traffic; each was responsible for screening vehicles that approached him or her. We were told that agents look for visual clues that could indicate drug or alien smuggling, as occurred in an incident we observed. During our visit, an agent told us that on the basis of such visual clues, he sent a vehicle to secondary inspection, where all passengers were later identified as illegal aliens. In another lane, closest to the center of the freeway, was a Pre-Enrolled Access Lane (PAL) which permitted vehicles to use an electronic transponder to move through more quickly than the normal traffic lanes. (Obtaining a transponder requires passing a background investigation; San Clemente is the only U.S. checkpoint with such a lane.) However, an agent was also positioned at the PAL lane, and during the period we were there, a vehicle that attempted to go through it without a transponder was ordered into secondary inspection, where it was determined that the occupants were illegal aliens. The I-5 checkpoint also performs checks on buses, which are to stop at the checkpoint, and on trucks, which are to transit the adjoining weigh station. The Border Patrol also screens trucks at that point, at times using the Vehicle and Cargo Inspection System (VACIS) machines, which use gamma-ray technology to examine the contents of vehicles. At the checkpoints, all suspected smugglers or illegal aliens are fingerprinted using the Automated Biometric Identification system and a law enforcement check is run on their fingerprints through the FBI’s Integrated Automated Fingerprint Identification System (IAFIS). If persons are determined to be undocumented aliens or are wanted for other offenses, detention facilities are available at the checkpoints. Border Patrol officials said that having the ability to perform fingerprint and law enforcement checks at the checkpoints enables them to quickly determine if detained persons are illegal aliens or have outstanding criminal complaints pending against them. Border Patrol officials told us that they had been conducting a project to identify the numbers of illegal aliens with criminal records that had been apprehended in areas around the Temecula and San Clemente checkpoints. For example, after matching fingerprints with IAFIS during a 6-week period from August to September 2004, they found that 157 illegal aliens with criminal records had been apprehended by Temecula Border Patrol agents. These illegal aliens had criminal records that included assault, burglary, and immigration offenses. Overall, during the 6-week period, 28 percent of Temecula’s and 22 percent of San Clemente’s apprehensions were illegal aliens with criminal records. The Border Patrol regards the I-5 and I-15 checkpoints as 24-hour checkpoints, closing them generally only for safety reasons. However, as we observed when we visited the two checkpoints, heavy traffic volume may preclude screening every northbound vehicle. As noted above, the I-5 checkpoint south of San Clemente is the busiest interior traffic checkpoint in the nation, with approximately 144,000 vehicles passing through daily, while the Temecula I-15 checkpoint ranks second, with approximately 122,000 vehicles daily. However, as we observed, and as San Clemente and Temecula checkpoint officials told us, when traffic backs up, the traffic checks are suspended and traffic is “flushed” through the checkpoint. Agents said that they know from experience how long a wait period traffic backups are likely to produce, and that they keep a close watch on how long the line has become. During our visit, we observed that Border Patrol agents monitored traffic and took action to avoid creating major traffic delays at these checkpoints. Since the Border Patrol agents may suspend their operations to avoid creating lengthy traffic delays, actual time that the agents stand out on the highway lanes and visually inspect traffic varies. Checkpoint records showed that at the I-5 checkpoint south of San Clemente, traffic was screened only about 36 percent of the time in fiscal year 2004, a reduction from about 57 percent in fiscal year 2003 and about 63 percent in fiscal year 2002. Temecula checkpoint traffic was screened only about 42 percent of the time in fiscal year 2004, down from about 63 percent of the time in fiscal year 2003. Border Patrol officials attributed these declines to a combination of insufficient staffing levels at the stations and the need to avoid imposing long traffic waits on the public. According to Temecula station officials at the time of our September 2004 visit, they had received no complaints for at least several months about traffic delays. We observed that the permanent checkpoints at San Clemente and Temecula had a range of capabilities to monitor and inspect vehicles and their occupants. These included concrete side aprons off the highway to permit more intensive cages and shade for canines, surveillance cameras for monitoring activities at the checkpoint and computers with hardline communications, detention facilities for holding smugglers and illegal aliens, and concrete side aprons with their own traffic lane to permit trucks to line up for VACIS gamma-ray inspections. In addition to manning the permanent checkpoints, the Border Patrol routinely sets up tactical checkpoints to reduce the chances of persons evading the permanent ones by using secondary roads. In particular, the Temecula checkpoint has eight locations where tactical checkpoints are established as needed based on intelligence on illegal immigration or related activity. We observed a tactical checkpoint on Sandia Creek road, south and west of the I-15 checkpoint, in a back hill rural area that had little traffic, but where the secondary road network could allow for evading checkpoints on the main highway (see fig. 13). At this tactical checkpoint, agents stopped each vehicle and talked to drivers and passengers; in contrast, at permanent checkpoints with heavy traffic volume, most vehicles are not stopped but are observed as they move slowly through the checkpoint lanes. The Tucson, Arizona, sector’s area of responsibility runs 261 miles along the U.S.-Mexico border from New Mexico to the Yuma County, Arizona, line; it is 90,530 square miles in area. The sector encompasses national parkland and parts of the Tohono O’odham Indian reservation, and its environment is like that of much of the southwest border—the terrain is inhospitable, consisting of mountains, flat desert, rolling brushland, and canyons. Summer temperatures can reach an average daily high of 100 to 110 degrees, and lack of shade for vast stretches of the border and inland areas can pose severe health hazards to those attempting to walk across the area. Most of the border in this sector is delineated by cattle fences and border markers, with little effective fencing of any kind, according to Border Patrol officials. Cattle fences can prevent cattle from crossing the border, but they are not designed or intended to prevent people from doing so, as they are essentially strands of wire with large gaps between them and are easily pushed apart, according to the officials. Agents patrol the border by truck, aircraft, horseback, ATVs, and bicycles and on foot; maintain traffic checkpoints along highways leading from border areas; and conduct antismuggling investigations. At the time of our October 2004 visit, the sector was headed by a chief patrol agent and staffed by 2,100 Border Patrol agents deployed throughout the sector from eight Border Patrol stations. Border Patrol operations in the Tucson sector have been the subject of legislative direction since fiscal year 1999; this direction applied to no other Border Patrol sector. For fiscal years 1999-2004, annual appropriations acts made no funds “available for the site acquisition, design, or construction” of any Border Patrol checkpoint in the Tucson sector. Since the Tucson sector had no permanent checkpoints in fiscal year 1999 (or before), the effect of this legislative language was that no permanent checkpoints could be planned or constructed in this sector. To comply with the congressional ban on funding for permanent checkpoints, and the congressional requirement to relocate checkpoints after a specified period of days, the Border Patrol told us that the sector maintains what we term nonpermanent checkpoints that, when open, are generally at the same locations, with the exception of one on I-19, from June 2002 through fiscal year 2004, and another on state highway 83. On I- 19, a major north-south interstate highway that runs from Nogales on the border north to Tucson, about 70 miles away, nonpermanent checkpoints were alternated between KP 42 and KP 25, 17 kilometers further south, from June 2002 through the end of fiscal year 2004. Starting in fiscal year 2005, the Border Patrol kept the checkpoint at the KP 42 location to preclude illegal entrants from taking advantage of its being moved southward to KP 25, as had regularly occurred. The checkpoint is kept open for 14 days, closed for 8 hours, then reopened for 14 days, and so forth, according to the Border Patrol. The Border Patrol states that it believes that this schedule conforms to the fiscal year 2005 legislative language requiring that Tucson sector checkpoints relocate “at least an average of once every 14 days.” Other checkpoints in the sector have been opened and closed on varying schedules in fiscal year 2005, but those schedules also conform to the law, according to the Border Patrol. To support these nonpermanent checkpoints, the Tucson sector operates tactical checkpoints periodically, as occurs in other sectors with permanent checkpoints. The tactical checkpoints function the same way as tactical ones in other sectors with permanent checkpoints. Figure 14 shows the sector and the approximate locations at which nonpermanent checkpoints may be located when open. According to the Border Patrol, it also alternates among three sites for checkpoints on state highway 83. (The approximate locations are shown as 83C MP54, 83C, and 82 in fig. 14). Because of safety issues, the nonpermanent checkpoints designated as SR 90, 80C and highway 191 do not have alternative sites. They are kept open for the legislatively permitted length of time, and then closed, according to the Border Patrol. Another checkpoint is open and closed about the same hours as a port of entry south of it on the border. However, the Border Patrol monitors sector night traffic with various means, such as roving patrols; these are sufficient, they told us, given the very light traffic in the sector at night. We observed the operations of the nonpermanent checkpoint on I-19, the north-south interstate highway that runs from Nogales on the border north to Tucson, about 70 miles away. According to Border Patrol officials, only limited routes are available to circumvent the I-19 checkpoint, primarily by driving or walking across countryside that can make smugglers or aliens relatively visible, because of vehicles raising dust in their wake. In fiscal year 2003, an average of over 15,000 vehicles passed through the I-19 checkpoint daily, including many commercial trucks, especially during produce season, according to the officials. The I-19 nonpermanent checkpoint consisted of a trailer, portable generators, water, and rest room facilities that were towed in; traffic warning signs; and orange traffic cones to designate the checkpoint area and to slow vehicles down to be inspected. At the time of our visit, the I- 19 checkpoint was located next to an overpass to provide some protection from the elements, since there was no canopy as is typically found at permanent checkpoints we visited in other sectors. Border Patrol officials also said that only two locations along I-19 are appropriate for checkpoint operations because of space and safety considerations. From June 2002 through the end of fiscal year 2004, the I-19 checkpoint was alternated between these two locations, at KP 42 and KP 25, relocating every 7 days. During fiscal year 2005, the checkpoint location has been maintained only at the northern location, as noted above, and is open for 14 days, then closed for 8 hours, and then reopened for 14 days. At the I-19 checkpoint locations, the Border Patrol has three lanes of northbound traffic to screen—two highway lanes and an off-ramp. The operation, consisting of Border Patrol agents and canines, was run out of a trailer, with a small detention room inside it, and a stand-alone computer not connected externally. There was no hardwired computer access to databases to check fingerprints or to validate identities through other law enforcement databases. Therefore, according to Border Patrol agents, they can process some reports on the computer but have to save information to a diskette and take it back to the station for further processing. Similarly, processing and fingerprinting of suspects must wait until the suspects are transported to a Border Patrol station with hardwired computers. During summer months, we were told, the temperature can reach about 130 degrees on the heated tarmac of the highway; as a result, canine performance and endurance are limited. According to the Border Patrol, equipment that must be relocated when the I-19 and other checkpoints are moved includes a minimum of 3 light generator plants; 1 generator; 1 portable toilet; 20-100 traffic cones; and 5 or more signs, showing “Stop,” “Checkpoint Ahead,” “Reduce Speed,” and similar warnings. In addition, the standard minimum deployment would be one processing trailer and detention area, two or more marked vehicles and a water trailer. The I-19 checkpoint at KP 42 had little area off-road to conduct secondary inspections, and that area consisted of dirt along the side of the highway. Border Patrol officials told us that to comply with legislative restrictions, they were unable to install anything that could be considered to create a permanent infrastructure, such as water lines, electricity, buried communication lines or towers, and buildings. Figure 15 shows the I-19 nonpermanent checkpoint near KP 42. We also observed the nonpermanent checkpoint on state highway 85, near Ajo, Arizona. According to Border Patrol officials, this checkpoint is located just south of where state highways 85 and 86 merge, both coming from the south, in order to ensure that all vehicles traveling north must go through the checkpoint. Only about 1,100 vehicles transit this checkpoint daily, we were told. As with the I-19 checkpoint, there were only limited portable equipment capabilities at the Ajo checkpoint. There was no overpass to provide shade. The Ajo checkpoint is shown in figure 16. The Laredo, Texas, Border Patrol sector covers 110,000 square miles, 116 counties or parts of counties extending north to the Oklahoma border, and approximately 171 river miles of common border with Mexico. The sector’s eastern border is the McAllen sector, its southern border is the Rio Grande, and its western border is the Del Rio sector. The sector’s international border represents about 10.6 percent of the southwest border, and includes the International Falcon Reservoir, sometimes called Falcon Lake, a 120-square-mile body of water that was formed by damming the Rio Grande in 1953. The southwestern side of the lake is controlled by Mexico, the northeastern side by the United States, with the international border running down an imaginary line through the middle. The sector’s diverse economic base includes portions of the Rio Grande Valley, with large, privately owned cattle ranches, other agribusiness, and a large volume of goods from Mexico that are trucked through the Laredo ports of entry into the United States, and which are then stored in warehouses while awaiting inspection and transfer into trucks for transport to the rest of the United States. According to Border Patrol officials, Laredo is one of the busiest commercial ports of entry in the United States. The sector landscape generally consists of rolling brushland, reservoirs, farmland, and urban flatland, with the more rural sections being fairly flat but also having dense undergrowth that can impede persons such as smugglers or illegal aliens attempting to walk off- road, according to Border Patrol officials. At the time of our January 2005 visit, the sector was headed by a chief patrol agent and staffed with 981 Border Patrol agents, deployed throughout the sector from eight Border Patrol stations. The sector had ATVs, helicopters, fixed wing aircraft, and patrol boats; the last are used to patrol the International Falcon Reservoir. The patrol boats are not used for Rio Grande patrol, but jet skis are used for swift water river rescues, according to Border Patrol officials. Approximately 80 canines are also assigned to traffic screening operations at the sector’s checkpoints. The sector has five permanent checkpoints that screen traffic 24 hours a day, 7 days a week, generally closing only for safety reasons, and utilizes up to six tactical checkpoints that are opened on an as-needed basis, according to Border Patrol officials. We visited two permanent checkpoints in the sector, on two-lane state highway 351, in the vicinity of Hebbronville, and on I-35, the major north-south interstate highway leading to and from Laredo and San Antonio. We also visited the construction site of a new, replacement permanent checkpoint for the existing one on I-35, about 10 miles north of the current location. That new checkpoint is scheduled to open in August 2005, according to Border Patrol officials. There are more secondary roads in the Laredo sector than in the neighboring McAllen sector; as a result, the Border Patrol maintains more permanent checkpoints and also utilizes tactical checkpoints. According to Border Patrol officials, tactical checkpoints are used during certain times of the year, depending on factors such as increases in traffic on secondary roads, and local, state, or national events being conducted in the area. The sector’s permanent and tactical checkpoints are strategically placed on roads and highways and at junctions that permit monitoring and inspection of vehicles leaving the border area, according to the officials (see fig. 17). According to the Border Patrol, traffic checkpoint operations are generally supported by local ranchers, who permit the Border Patrol to enter their fenced property. The ranchers also permit the Border Patrol to place sensors at locations that could be favored by smugglers, according to Border Patrol officials. We observed the operations of two permanent checkpoints in the Laredo sector; on I-35, about 15 miles north of Laredo, and another on state highway 359 between Falfurrias in the McAllen sector and Laredo. As was the case with other checkpoints we visited in this and the McAllen sector, the checkpoints had a tollbooth-like area with at least two traffic lanes, one reserved for passenger cars and trucks, and the other for commercial trucks and buses (see fig. 18). At the time of our visit, the I-35 checkpoint was staffed with one supervisor, six agents, and canines. The facility consisted of a trailer that contained IAFIS fingerprinting equipment, three holding areas for apprehended illegal aliens, and video cameras (including infrared for nighttime use) to monitor activities in and around the checkpoint. Border Patrol agents told us that I-35 vehicle traffic wait time has not been more than 20 to 30 minutes, and generally takes place around 2:00 p.m. We observed a lift that could be used to inspect under vehicles, but did not observe trucks being examined by gamma ray equipment. We asked whether VACIS equipment was available to screen trucks with gamma ray as we had seen at other checkpoints, and the agents told us that VACIS trucks were not permanently located at the checkpoint but are made available periodically by the official port of entry if they are requested. As was the case for checkpoints in the McAllen sector, those in the Laredo sector are directed to inspect every vehicle that is proceeding northward, according to Border Patrol officials. Because there are few north-south roads in the sector, an absence of secondary roads to go around the checkpoints, and manageable volume of traffic, it is possible to screen all vehicles transiting the checkpoints, according to Border Patrol officials. As we observed, each vehicle was sniffed by a canine, and occupants were questioned by a Border Patrol agent. We were told that the agents are able to process a vehicle on average in about 9 seconds. The checkpoint at I-35 averages about 13,600 transiting vehicles daily, according to the Texas Department of Transportation; of these, about 36 percent are trucks. Border Patrol agents at the highway 359 checkpoint outside of Hebbronville (see fig. 19) told us that they had recently apprehended a number of “brush walkers,” illegal aliens who had been walking through the brush surrounding the checkpoint to evade apprehension at the checkpoint. The agents said that smugglers will drop off a load of aliens just short of the checkpoint so that they can attempt to walk around to a point where they would be picked up again. However, the agents said that it is very difficult terrain to traverse, even along ranch and pipeline trails, which are monitored by several means, including electronic surveillance. The agents further stated that local ranchers are very supportive of the Border Patrol activities in the area and have provided keys to their ranches for access when intrusions are detected, or when the ranchers themselves call to notify agents that suspected illegal aliens are on the property. Figures 19 and 20 show two checkpoints in the sector. The Laredo checkpoints we observed had a wide range of capabilities to screen vehicles and their occupants. These included permanent tollboth-like structures that provide cover from the weather, including shade for agents and canines; lifts to permit inspection of undersides of vehicles; computers with hardwired communications and databases to permit investigation into those detained; detention facilities; and concrete side aprons with their own traffic lanes to permit trucks to line up with off highway room for inspections. As noted, a new I-35 checkpoint is scheduled to open in August 2005, about 10 miles north of the current location. Border Patrol officials told us that one major advantage of the new location is that it will not be within sight of warehouses or other structures, which they said currently provide cover for smugglers to observe the operations at the existing I-35 checkpoint. The new checkpoint, which will cost about $12 million to construct, will be able to accommodate six lanes of vehicles, with separate lanes for passenger vehicles and trucks, along with a large area for inspecting and unloading trucks, if necessary (see fig. 21). The McAllen, Texas, Border Patrol sector covers 18,584 square miles, 19 counties, and approximately 316 river miles of common border with Mexico. According to Border Patrol officials, the sector’s area of responsibility runs from the mouth of the Rio Grande at the Gulf of Mexico to the Zapata/Starr county line, where it meets the Laredo sector. The sector’s international border represents about 9.4 percent of the southwest border; its southern edge follows the Rio Grande through Brownsville, emptying into the Gulf of Mexico. Large parts of the sector, which includes a portion of the Rio Grande Valley, are privately owned ranches, including the well-known King Ranch, which is approximately 800,000 acres in size. Although the land in the sector is fairly flat, it receives sufficient precipitation to permit growth of dense sage, scrub brush, and cacti. This has created an inhospitable environment for persons such as smugglers or illegal aliens attempting to walk off-road, as the brush is so thick that it can actually block foot traffic or can severely injure persons trying to negotiate it, according to Border Patrol officials. At the time of our February 2005 visit, the sector was headed by a chief patrol agent and staffed with 1,465 Border Patrol agents, deployed throughout the sector from nine Border Patrol stations. The sector had ATVs, helicopters, patrol boats, and fixed wing aircraft. The sector also utilizes bicycle patrols around the ports of entry and downtown areas, and video monitors and electronic sensors placed along the border to detect people or vehicles attempting to enter the country illegally. Only two major north-south highways in the sector lead away from the border: U.S. highways 281 and 77. The Border Patrol has permanent checkpoints on both, at Falfurrias and Sarita, respectively. Both checkpoints are approximately 80 miles inland from the international border and are roughly parallel to each other, although about 25 miles apart (see fig. 22). Border Patrol officials told us that the combination of only two north-south highways and the absence of secondary roads make it unnecessary to establish tactical checkpoints in support of the permanent ones. The checkpoints at Falfurrias and Sarita cannot be easily evaded by walking or driving around them, given the terrain, fenced private ranches, detection sensors, and lack of secondary roads, Border Patrol officials stated. Much of the land near the Border Patrol checkpoints on U.S. highways 281 and 77 is private ranch land that is both heavily fenced and actively patrolled by private security forces, according to Border Patrol officials. As in the Laredo sector, checkpoint operations are supported by the local ranchers, according to the Border Patrol, who permit the Border Patrol to enter their fenced property to apprehend illegal entrants. We observed the operations of the Falfurrias permanent checkpoint on U.S. highway 281, a major north-south highway that runs from McAllen on the border north toward San Antonio, Texas (see fig. 22). This checkpoint (and the one on U.S. highway 77, which we did not visit) had a tollbooth- like area with at least two traffic lanes, one reserved for passenger cars and trucks, while the other is for commercial trucks and buses. At both checkpoints, Border Patrol agents are to stop and screen every vehicle that is proceeding northward. As we observed, each vehicle was sniffed by a canine, and its occupants were questioned by a Border Patrol agent. We also observed a bus being searched, after a canine got a “hit,” indicating possible drugs. The agents found three 30-pound packages of marijuana in the engine compartment. According to Border Patrol officials, the agents process a vehicle in about 9 seconds and average about 14,900 vehicles—about 40 percent trucks—a day transiting the checkpoints. This volume of traffic allows for agents to stop and question occupants of each vehicle, compared with the 144,000 vehicles daily going through the California checkpoint on I-5 south of San Clemente. There is little need to use tactical checkpoints in support of the permanent ones in the McAllen sector, according to Border Patrol officials, because a lack of secondary roads and geography that is not easily traversed force smugglers and illegal aliens to attempt to proceed through the checkpoints on U.S. highways 281 and 77. This situation is in contrast to the Tucson and San Diego sector operations, where tactical checkpoints on secondary roads are constantly being used to support the permanent checkpoints because of the many different routes leading away from the border that are available to smugglers and illegal aliens. The permanent checkpoints on U.S. highways 281 and 77 had a wide range of capabilities and facilities to screen vehicles and their occupants. These included permanent tollbooth-like structures that provide cover from the weather, including shade for agents and canines; lifts to permit inspection of undersides of vehicles; computers with hardwired communications and databases to provide detention facilities; and concrete side aprons away from main traffic lanes that permit trucks to safely line up with sufficient room for a VACIS gamma-ray vehicle to pass over and inspect them. Figure 23 shows several photos of the checkpoint on U.S. highway 281, near Falfurrias, Texas. In addition to the contact named above, Leo Barbour, Katherine Davis, Darryl W. Dutton, Ann H. Finley, Lemuel N. Jackson, James R. Russell, and Jonathan R. Tumin made key contributions to this report.

Summary: The U.S. Border Patrol, a component of the U.S. Customs and Border Protection (CBP) agency, a part of the Department of Homeland Security (DHS), aims to apprehend persons who illegally enter the United States between official ports of entry, including potential terrorists, aliens, and contraband smugglers, thereby deterring or stopping illegal activity. The Patrol operates permanent and tactical (temporary) interior traffic checkpoints on major and secondary U.S. roads, mainly in the southwest border states where most illegal entries occur, as part of a multi-layer strategy to maximize detection and apprehension of illegal entrants. This report addresses (1) the role of interior checkpoints in the Patrol's strategy; (2) what is known about checkpoint costs and benefits; and (3) how checkpoints are evaluated and what performance measures indicate regarding their effectiveness. The Border Patrol operates 33 permanent traffic checkpoints in 8 of its 9 sectors in the southwest border states, supported by tactical checkpoints. While permanent checkpoints have the advantage of physical infrastructure, tactical ones have the mobility to block routes used to evade permanent ones and to respond to intelligence on illegal activity. A third type of checkpoint operates in the Tucson, Ariz., sector, where the Patrol has been legislatively prohibited from funding construction of checkpoints since fiscal year 1999. This restriction has prevented checkpoint construction. The Patrol also began closing or relocating checkpoints in the sector every 7 days at the instruction of congressional staff in June 2002, and was legislatively required to relocate checkpoints on the same schedule in FY 2003 and 2004, and an average of once every 14 days in FY 2005. Three of six checkpoints in the sector had to close for 7/14 days, as safety considerations made it too hazardous to relocate them. Local law enforcement and business and community leaders we interviewed from communities near interior traffic checkpoints said that benefits resulting from checkpoint operations included reductions in crime and vandalism. Although a few cited traffic delays, most were supportive of checkpoint operations. However, some others were concerned about the impact of the checkpoints on traffic congestion and quality of life in their communities. The Border Patrol does not routinely evaluate the effectiveness of checkpoint operations, or their costs. The Patrol includes limited traditional performance measures in its Performance and Annual Report, such as apprehensions and contraband seized. GAO developed an apprehension per agent work year measure to assess performance. The data suggest that the performance of the Tucson sector interior checkpoints dropped starting in FY 2002, and more in FY 2003, after the Border Patrol began relocating or closing them on a regular basis. Three other sectors we visited that did not have to relocate or close checkpoints experienced no comparable decrease in apprehensions per agent work year during the same time period. Other factors not measured or accounted for might also have contributed to these outcomes, but the Border Patrol's limited measures do not capture or assess them. A broader range of performance measures, when considered with other indicators, could be useful to CBP and the Congress as they consider ways to improve the effectiveness of interior traffic checkpoints and border security efforts.