Within INS, the Border Patrol is the agency responsible for securing the border between the ports of entry. The Border Patrol's mission is to maintain control of the international boundaries between the ports of entry by detecting and preventing smuggling and illegal entry of aliens into the United States. In addition, in 1991, ONDCP designated the Border Patrol the primary agency for narcotics interdiction between the ports of entry. To accomplish its mission, the Border Patrol (1) patrols the international boundaries and (2) inspects passengers and vehicles at checkpoints located along highways leading from border areas, at bus and rail stations, and at air terminals. The Border Patrol uses vehicles and aircraft to patrol areas between the ports of entry and electronic equipment, such as sensors and low-light-level televisions, to detect illegal entry into the country. The Border Patrol carries out its mission in 21 sectors. Nine of these sectors are located along the southwest border with Mexico. As of September 30, 1994, about 3,747 agents were assigned to the 9 sectors, representing 88 percent of Border Patrol agents nationwide. The following other federal entities support land border control efforts between the ports of entry along the southwest border. El Paso Intelligence Center (EPIC), the nation's principal tactical drug intelligence facility, prepares assessments on the threat of drug smuggling. Operation Alliance prepares border control strategies and coordinates drug enforcement activities of 17 federal and numerous state and local law enforcement agencies combating drug smuggling. Joint Task Force Six (JTF-6), located in El Paso, coordinates military support for drug enforcement efforts. In September 1991, ONDCP tasked Sandia National Laboratories, through INS, to do a "systematic analysis of the security along the United States/Mexico Border between the ports of entry and to recommend measures by which control of the border could be improved." ONDCP chose Sandia because of its expertise in designing physical security systems. In January 1993, Sandia issued its report entitled Systematic Analysis of the Southwest Border. We refer to this as the Sandia study throughout our report. According to the study, to conduct its analysis, Sandia personnel visited all nine Border Patrol southwest border sectors, toured various Border Patrol facilities, and interviewed both chief patrol agents and Border Patrol agents. They viewed much of the southwest border from either the ground or the air and reviewed a number of previous studies related to border control. In addressing our objectives to (1) determine the extent of the threat from drug smuggling and illegal immigration and (2) identify ways to enhance security between the ports of entry, we interviewed intelligence officials responsible for determining the threat from drug smuggling and illegal immigration and reviewed related documentation; reviewed the Sandia study and discussed the study's findings with its authors and various INS officials responsible for border control; reviewed EPIC, Department of State, and Operation Alliance reports to determine the threat from drug smuggling; visited the San Diego and El Paso Border Patrol sectors and discussed with sector officials their recent border control initiatives; analyzed INS data from its management information systems related to apprehensions and narcotics seizures to obtain additional information on the threat from drug smuggling and illegal immigration along the southwest border; and interviewed INS headquarters officials to determine plans for improving border security. As agreed with the Subcommittee, our focus was control of the land border between the ports of entry. We did not evaluate border control activities at the ports of entry or efforts related to smuggling by air and sea. We did not verify the accuracy and completeness of the data we obtained from INS' management information systems. We did our work between October 1993 and September 1994 in accordance with generally accepted government auditing standards. We discussed the results of our work with the Acting Chief of the Border Patrol and other INS officials. Their comments are presented on page 27. Although the full extent is unknown, drug smuggling is a serious threat along the southwest border. The Department of State's 1993 International Narcotics Control Strategy Report indicated that Mexico is a transit country for South American cocaine destined for the United States and a major country of origin for heroin and marijuana. According to the report, between 50 and 70 percent of the cocaine smuggled into the United States transited Mexico, entering primarily by land across the southwest border. In addition, about 23 percent of the heroin smuggled into the United States originated in Mexico. INS data showed that Border Patrol narcotics seizures along the southwest border have risen over the last few years. Between fiscal years 1990 and 1993, the number of Border Patrol narcotics seizures rose from around 4,200 to around 6,400, an increase of about 50 percent. The amount of cocaine seized nearly doubled from about 14,000 pounds in 1990 to about 27,000 pounds in 1993. According to a June 1992 Operation Alliance report, the primary smuggling route across the southwest border was by land. The report pointed out that although cocaine was the primary drug threat, followed by marijuana, the heroin threat was growing. The report stated that in spite of law enforcement agencies' efforts to counter drug smuggling, the flow of drugs between the ports of entry along the southwest border continued due to vast open areas and a relatively low law enforcement presence. The report concluded that "our successes are insignificant when compared to the threat. Our collective efforts are currently only a minor irritant to the smugglers." The Sandia study deemed drug smuggling a serious threat all along the southwest border. For example, the study deemed drug smuggling a serious threat in south Texas and the southern Arizona border area, which is dubbed "Cocaine Alley." Figure 1 shows the seizure of over 1,000 pounds of cocaine by Border Patrol agents in San Diego. Figure 2 shows a panel truck stopped by El Paso Border Patrol agents (see fig. 2A), with narcotics hidden in its interior panels (see fig. 2B). Agents seized nearly 250 pounds of marijuana (see fig. 2C). Illegal immigration is also a serious threat to the United States. In 1993, we estimated that the total inflow of illegal aliens into this country in 1988 ranged from 1.3 million to 3.9 million. The major component of the inflow, 1.2 million to 3.2 million, was Mexicans crossing the southwest border, with most entering between the ports of entry. Much of the inflow represented short-term visits to the United States. In June 1994, INS estimated there were about 3.8 million undocumented migrants residing in the United States. About half of the unlawful residents entered unlawfully across the borders, while the other half entered as visitors but did not leave. The estimates were based on an analysis of INS and Bureau of the Census data and, according to INS, experts have embraced these estimates as the best available. The 1993 Sandia study characterized the southwest border as "being overrun." For example, in the San Diego sector, the study noted that as many as 6,000 aliens attempted to enter the United States illegally every night along the first 7-1/2 miles of border beginning at the Pacific Ocean. One of the reasons given in the study for this situation was that most of the border fencing in the San Diego sector and other urban areas was "poorly maintained" and "totally ineffective" (see fig. 3). However, as discussed on page 15, INS recently completed a new fence in the San Diego sector and plans additional fencing in other sectors. Border Patrol apprehensions along the southwest border declined between 1986 and 1989 but, although still below the 1986 level, apprehensions have gradually risen since then (see fig. 4). Figure 5 illustrates the prominence of the San Diego and El Paso sectors as border-crossing locations. In fiscal year 1993, these two sectors accounted for two-thirds of the 1.2 million southwest border apprehensions. Although the southwest border is approximately 1,600 miles long, much of it is difficult to cross by foot or vehicle due to rugged terrain, desert, or natural barriers such as some portions of the Rio Grande River. Our analysis of INS data showed that in fiscal year 1992 over half of all southwest border apprehensions occurred along only 18 of the 1,600 border miles--13 miles along the border between San Diego and Tijuana, Mexico, and 5 miles along the border between El Paso and Ciudad Juarez, Mexico. However, as we discussed on pages 23 to 25, recent border control initiatives in San Diego and El Paso appear to have rerouted some illegal immigrants to other southwest border areas. Unless border control efforts become more effective, illegal immigration is expected to increase. In September 1993, we reported that the flow of illegal aliens across the southwest border is expected to increase during the next decade because Mexico's economy is unlikely to absorb all of the new job seekers that are expected to enter the labor force. The Border Patrol's traditional tactic of discouraging illegal entry has been to apprehend aliens once they have entered the United States. According to the Sandia study's authors, this tactic was inefficient and diminished the Border Patrol's ability to control the border. In addition, the authors said the only good border control strategy is one that prevents people from crossing the border. The study concluded that the way to prevent illegal entry is to impose "effective barriers on the free flow of traffic." The study noted that where it is not possible or practical to keep drugs and illegal aliens from entering the United States, they should be stopped at the earliest opportunity. In addition, the Sandia study concluded that "control of the illegal alien and drug traffic can be gained" and recommended that the Border Patrol change its tactics from apprehending illegal aliens after they have entered the United States to preventing illegal entry into the United States. A goal of a "prevention" strategy would be to significantly increase the difficulty of crossing the border illegally. The Sandia study concluded that single barriers, which had been used thus far, had not proven effective in preventing either drugs or illegal aliens from entering the country. Consequently, the study recommended (1) multiple lighted barriers in urban border areas to prevent the entry of large volumes of drugs and illegal aliens, with patrol roads between the barriers and (2) enhanced checkpoint operations to prevent those drugs and illegal aliens that succeeded in crossing the border from leaving the border area. (See fig. 6 for an artist's illustration of the Sandia study's proposed three-fence barrier system.) According to the Sandia study, multiple barriers in urban areas would provide the Border Patrol a greater ability to (1) discourage a significant number of illegal border crossers, (2) detect intruders early and delay them as long as possible, and (3) channel a significantly reduced level of traffic to places where border patrol agents can adequately deal with it. The Sandia study recommended multiple barriers along approximately 90 miles, or less than 6 percent of the southwest border. Because of rugged terrain, segments of the southwest border cannot be controlled at the immediate border. The alternative the Sandia study recommended for these areas is to use highway checkpoints to contain those aliens who cross the border illegally. The study recommended more checkpoints be established and that all operate full time. The Border Patrol's use of part-time checkpoints allows violators to cross unobserved after the checkpoint is closed. Except for the proposed multiple-fence system, many of the Sandia study's recommendations were not new and, according to Border Patrol officials, had been made previously by their own personnel. For example, a January 1989 study recommended many of the same measures such as barriers, checkpoints, and enhanced electronic surveillance equipment. The study was conducted by a retired head of the Border Patrol for the Federation for American Immigration Reform. The Sandia study estimated it would initially cost an additional $260 million to implement its recommendations with annual recurring costs of about $69 million. Most of the initial costs are associated with physical barriers and checkpoints. Ultimately, implementing the Sandia study's recommendations may require only a slightly larger Border Patrol force. According to the study, as physical barriers and checkpoints were completed, the number of Border Patrol agents required would increase. However, the study noted that as control was gained at the border, the number of agents could be allowed to decrease to a number not significantly larger than the 3,640 agents that were deployed along the southwest border when the study began in December 1991. The Border Patrol officials we spoke with (including the acting chief, acting deputy chief, San Diego and El Paso chief patrol agents, and a regional Border Patrol official) all agreed with the Sandia study's conclusion that the Border Patrol should focus on preventing illegal entry rather than on apprehending illegal aliens. In addition, officials of EPIC, Operation Alliance, JTF-6, and the mayor and police officials of El Paso support the concept of trying to prevent entry rather than apprehending aliens. This strategy is also in line with our past positions on controlling illegal immigration. In June 1993, we testified before the House Subcommittee on International Law, Immigration and Refugees, Committee on the Judiciary, that "the key to controlling the illegal entry of aliens is to prevent their initial arrival." Major Border Patrol initiatives in the San Diego and El Paso sectors are consistent with the Sandia study's findings. Both sectors have begun initiatives that focus on preventing illegal entry rather than on apprehending aliens. In 1990, the San Diego sector's chief patrol agent began an initiative to erect physical barriers, primarily to deter drug smuggling. With the assistance of JTF-6, the San Diego sector installed 10-foot welded steel fencing along approximately 14 miles of border where sector officials believed the majority of drugs and illegal aliens crossed within the sector. The new fence, completed in late 1993, is substantially stronger than previous chain link fencing. JTF-6 is also installing high-intensity lights and a second and third fence at strategic locations along the same 14 miles. As of February 1994, JTF-6 had installed lights along about 4-1/2 of the 13 miles. The Sandia study recommended similar measures. For example, the study recommended that the sector erect multiple lighted physical barriers along the same stretch of border where the sector erected its new fence. Before September 1993, like San Diego, the El Paso sector's strategy emphasized apprehending aliens rather than preventing illegal entry. However, as apprehensions increased so did the opportunities for confrontation between illegal aliens and El Paso Border Patrol agents. These increased opportunities for confrontation led to allegations of abuse against agents. Under the sector's apprehension strategy, El Paso's chief patrol agent told us that the border area was in "complete chaos." The chief estimated there were up to 8,000 to 10,000 illegal border crossings daily, and only 1 out of 8 aliens was apprehended. The apprehension strategy also created several problems in the community. El Paso citizens and others complained about this approach in meetings with the sector's chief patrol agent. They believed that the Border Patrol did not try to prevent entry but, in fact, used the increased numbers of apprehensions as a primary factor in justifying its budget. Some local residents felt their civil rights were being violated by the Border Patrol. For example, students and teachers at a local high school filed a federal lawsuit to stop harassment after El Paso sector agents confronted a coach believing he was an alien smuggler.Illegal aliens also had a significant impact on the city's crime rates. El Paso police officials estimated that undocumented aliens committed 75 to 80 percent of all auto thefts, as well as many burglaries. The Mayor of El Paso told us that illegal immigration costs the city about $30 to $50 million per year. In light of these problems, El Paso's chief patrol agent began an initiative in September 1993 to change the sector's border control strategy to one of preventing illegal entry. The sector stationed all available agents immediately at a 20-mile stretch of the border in highly visible Border Patrol vehicles. The primary goal of the new strategy--Operation Hold-the-Line--was preventing significant numbers of aliens from entering the El Paso metropolitan area. Those who still tried to cross the border illegally were routed to less populated areas where they could be more easily apprehended. The El Paso sector's goal of preventing illegal entry is similar to the one recommended by the Sandia study, although the tactics are different. Sandia recommended multiple physical barriers to prevent entry; the sector employs agents as a human barrier. However, the sector eventually plans to construct additional lighted fencing, which is generally consistent with the Sandia study recommendations. Preliminary results in San Diego and El Paso suggest that the prevention strategy has reduced illegal entry in these sectors. Other benefits include less border crime, less confrontation between Border Patrol agents and illegal aliens, and strong public support. Although the San Diego sector's border control initiative has not been fully implemented, indications are that the new tactics are reducing the number of aliens crossing the border illegally in the San Diego area. As shown in figure 7, sector apprehensions were down 20 percent in fiscal year 1994 compared to 1992 and dropped below 1990 levels, the year the sector began implementing its new border control tactics. Apprehensions decreased even though the sector increased the amount of time spent on border enforcement nearly 41 percent between 1990 and 1994. Also, apprehensions at highway checkpoints away from the border declined 24 percent between fiscal years 1990 and 1993 even though the amount of time spent performing traffic checks increased 22 percent. During our review, we toured the most heavily trafficked portion of the San Diego sector border and found visible evidence of the new tactics' effect on illegal border crossing. As figure 8A shows, before the new border control tactics, hundreds of aliens would line up along the U.S. side of the border during daylight hours, waiting for an opportunity to go northward. However, as illustrated in figure 8B, after the new border patrol tactics were initiated, large groups of aliens no longer waited to cross during the day, which according to a Border Patrol official is typical. Also, as shown in figure 8C, formerly there were large gaps in border fencing allowing aliens to easily cross the border. However, figure 8D shows that these gaps in the fencing have now been closed. In addition, according to San Diego sector officials, violent crime and confrontations between Border Patrol agents and illegal aliens have been reduced because the fencing has prevented large groups of aliens from gathering. For example, murders in the border areas adjacent to the fencing dropped from nine in 1990 to none between 1991 and June 1994. According to the sector's chief patrol agent, as of February 1994, there had not been any incidents during the last 2 years where San Diego Border Patrol agents had used deadly force against illegal aliens. Also, reported incidents of assaults, rapes, and robberies in this area have declined. El Paso sector officials cited several indications that the sector's new prevention strategy is working. For example, according to the Border Patrol, the number of aliens attempting to illegally cross the border through the El Paso sector has decreased significantly. According to the chief patrol agent, before Operation Hold-the-Line, there were up to 10,000 illegal border crossings daily. In February 1994, the sector estimated that only about 500 people a day were illegally crossing the border. A March 1994 sector intelligence report indicated the new strategy had deterred many aliens in Mexico's interior from coming to the El Paso border area. There has been a sharp drop in El Paso sector apprehensions since implementation of its new strategy. As figure 9 shows, the El Paso sector's illegal alien apprehensions in fiscal year 1994 were down 72 percent compared to fiscal year 1993. Two factors influencing this decrease are the deterrent effect of the new border control strategy and, as discussed on pages 23 to 25, the rerouting of some illegal aliens to other southwest border areas. According to sector officials, many illegal border crossers try to leave El Paso via the airport. With the implementation of the prevention strategy in the El Paso sector, the number of apprehensions made at El Paso's International Airport was significantly reduced, indicating that fewer aliens are crossing the border illegally in El Paso. According to INS data, in fiscal year 1993, the sector averaged about 3,700 apprehensions a month at the airport. As of June 1994, the sector was averaging about 700 apprehensions a month, an 81-percent decrease. The El Paso public strongly supports the sector's new strategy. A poll taken in February 1994 showed 84 percent in favor of the sector's strategy.Complaints against the Border Patrol from both local residents and illegal aliens have decreased since the start of Operation Hold-the-Line. According to sector officials, only one allegation of abuse was made in the first 5 months of the operation. Although they did not have any specific data, local police officials said complaints to the police department of harassment by Border Patrol officers are "way down." Police officials also attribute a drop in certain crimes to Operation Hold-the-Line. For example, there were nearly one-third fewer burglaries and one-fourth fewer motor vehicle thefts in the 3 months after the operation began in September 1993 than in the same 3 months in 1992. Two studies also concluded that Operation Hold-the-Line has been successful in deterring illegal immigration in El Paso. A December 1993 study of Operation Hold-the-Line by the Center for Immigration Studies concluded that the operation "has proven to be successful" and the new preventative deployment was "both more humane and more effective." According to this study, the operation represented a viable long-term approach to more successful border control. A July 1994 study requested by the U.S. Commission on Immigration Reform found that the operation significantly reduced illegal crossings and had resulted in less crime and fewer allegations against Border Patrol agents in El Paso. In addition, the study found that the strategy has broad public support. However, the study also found that the redeployment of agents and longer work shifts have eroded morale among agents, and the strategy is labor-intensive. Any expansion without additional agents would stretch present resources. Although successful in significantly reducing illegal entry into El Paso, according to sector officials, the new strategy weakened some sector operations. For example, the El Paso sector took important resources from checkpoint operations resulting in some checkpoints being closed over 50 percent of the time. The Sandia study, however, recommended that El Paso increase the number of checkpoints and operate all checkpoints 24 hours a day. The San Diego and El Paso sectors' initiatives appear to have rerouted drugs and illegal aliens to other parts of the southwest border. For example, the July 1994 study of Operation Hold-the-Line found that the operation had less of an effect on those illegal aliens headed for the interior of the United States. These aliens apparently adapted to the prevention strategy by finding new routes into the United States. In addition, interviews with apprehended illegal aliens have revealed that smugglers are now telling those traveling from the interior of Mexico that it is easier to cross into Nogales, AZ, rather than into San Diego or El Paso, according to Tucson's Deputy Chief Patrol Agent. In addition, according to the deputy, some smugglers are reported to be moving their operations from San Diego to Nogales. A comparison of Tucson and El Paso sector apprehensions appears to support the premise that the recent San Diego and El Paso initiatives have increased illegal entry through other southwest border sectors. As figure 10 shows, since the start of the initiative in the El Paso sector, Tucson sector apprehensions have increased about 50 percent (about 93,000 in fiscal year 1993 compared to 139,000 in fiscal year 1994). El Paso apprehensions, on the other hand, dropped 72 percent (about 286,000 to about 80,000 over the same period). Another indication that illegal alien entry may be moving to other sectors is that while the San Diego sector's fiscal year 1993 apprehensions were 6 percent lower than fiscal year 1992, apprehensions in the remaining southwest border sectors increased about 17 percent (see fig. 11). Drug trafficking has also apparently been affected. According to EPIC's December 1993 Monthly Threat Brief, El Paso's Operation Hold-the-Line has lead to changes in smuggling methods. Instead of fording the Rio Grande River, some smugglers have attempted to move drugs through ports of entry and to areas east and west of El Paso, around the sector's 20-mile line of agents. According to a San Diego sector official, the new fence has virtually eliminated the number of drug and alien smugglers driving across the border in the San Diego area. However, the sector has noticed an increase in drug smuggling in the mountainous areas east of San Diego. In addition, the amount of cocaine seized in the El Centro sector, the sector adjacent to San Diego, increased dramatically from 698 pounds in fiscal year 1991 to nearly 18,000 pounds in fiscal year 1993. In August 1994, the INS Commissioner approved a national Border Patrol strategic plan for gaining control of the nation's borders. The strategy focuses on preventing illegal entry and builds on the success INS has reportedly had in San Diego and El Paso. INS plans to put more agents along the border and use more lighting, fencing, and other barriers. On the basis of the national border control strategy, each southwest border sector developed its own strategy identifying specific actions that need to be taken. INS plans to use a phased approach to implementing its border control strategy. In its first phase, INS plans to focus its resources in the two sectors where most illegal immigration has traditionally occurred--San Diego and El Paso. As border control is improved in San Diego and El Paso, INS anticipates that other areas will experience an increase in illegal entry. Therefore, the second phase targets the Tucson sector and the south Texas area. The third phase targets the rest of the southwest border, and phase four targets the rest of the U.S. border. INS has identified certain indicators that it plans to use in each of these phases to determine whether its efforts are successful. The proposed indicators include (1) an eventual reduction in apprehensions and recidivism, (2) an increase in attempted fraudulent admissions at ports of entry, (3) a shift in the flow to other sectors, and (4) fewer illegal immigrants in the interior of the United States. To achieve border control, the strategy recognizes the need to coordinate with other INS programs as well as other federal agencies such as the Department of Defense, Customs Service, and the Drug Enforcement Administration, as well as state and local law enforcement agencies. INS officials told us that it will take several years to implement the strategy and that INS did not have a specific time frame or cost figures for these improvements. INS officials believe that technology improvements, such as improved fencing and surveillance cameras, would make border control strategies more effective. According to the Acting Chief of the Border Patrol, these improvements would reduce the need for significant numbers of additional agents. INS plans to closely monitor the strategy's progress to determine the appropriate mix of personnel and other types of resources needed to gain control of the U.S. border. We believe the new national border control strategy shows promise for reducing illegal entry since the strategy (1) builds on the reported success the San Diego and El Paso sectors have had in reducing illegal immigration, (2) is consistent with recommendations made in previous comprehensive studies conducted by border control and physical security experts, and (3) has widespread public and government support. However, since it will take several years to implement the strategy, it is too early to tell what impact it will eventually have on drug smuggling and illegal immigration along the southwest border. On October 25, 1994, we met with the Acting Chief of the Border Patrol and other INS officials to discuss the results of our work. These officials generally agreed with the information and conclusions presented in this report. They emphasized the importance of sustained financial support to fully implement the national border control strategy. We plan no further distribution of this report until 30 days from its issue date, unless you publicly release its contents earlier. After 30 days, we will send copies of this report to the Attorney General, the Commissioner of the Immigration and Naturalization Service, the Director of the Office of National Drug Control Policy, and other interested parties. We will also make copies available to others upon request. 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Summary:
Pursuant to a congressional request, GAO reviewed U.S. efforts to secure the southwest border, focusing on: (1) the extent to which border security is threatened by drug smuggling and illegal immigration; and (2) ways the United States can enhance security between ports of entry. GAO found that: (1) although the full extent of drug smuggling and illegal immigration is unknown, both pose serious security threats along the U.S. southwest border; (2) despite U.S. law enforcement efforts, the flow of cocaine and illegal immigrants continues and is expected to increase; (3) a 1993 study on ways to enhance security along the southwest border between ports of entry recommended that the Border Patrol emphasize entry prevention instead of apprehension, construct physical barriers, and set up additional highway checkpoints to prevent entry; (4) although there is increased interest in a national entry prevention strategy, many officials believe that drug smuggling and illegal immigration activities have merely been rerouted to other southwest border areas where enforcement is less effective; (5) the Immigration and Naturalization Service (INS) plans to implement a national strategy that focuses on preventing illegal entry; and (6) it is too early to assess what impact the new INS strategy will have on drug smuggling and illegal immigration along the southwest border.