NAFTA, which was agreed to by Canada, Mexico, and the United States in 1992 and implemented in the United States through legislation in 1993, contained a timetable for the phased removal of trade barriers for goods and services between the three countries. Beginning December 18, 1995, Mexican trucking companies were to have been able to apply for the authority to deliver and backhaul cargo between Mexico and the four U.S. border states. However, on that date the Secretary of Transportation announced an indeterminate delay because of safety and security concerns. NAFTA’s timetable calls for all limits on cross-border access (i.e., truck travel within the three countries) to be phased out by January 2000. Until expanded access is granted, trucks from Mexico continue to be limited to commercial zones along the border (generally, areas between 3 and 20 miles from U.S. border towns’ northern limits, depending on each town’s population). For several decades, the United States has been expanding inspection and enforcement programs nationwide to encourage safer U.S. trucks and truck operation. DOT has, among other things, (1) issued minimum safety standards for trucks and commercial drivers, (2) provided grants to states to develop and implement programs that would lead to the enforcement of these safety standards, and (3) conducted reviews of about one-third of all domestic interstate trucking companies in order to determine overall compliance with safety regulations. Through the Motor Carrier Safety Assistance Program (MCSAP), DOT works in partnership with states to enforce federal truck regulations. As the states adopt federal safety regulations, DOT provides financial assistance for enforcement. Although DOT maintains a presence in all states to promote truck safety and requires that states comply with minimum federal regulations and requirements related to truck safety, it relies on the states to develop their own strategies for enforcement. NAFTA also established the Land Transportation Standards Subcommittee to work toward compatible truck safety and operating standards among the countries. While U.S. and Canadian commercial trucking regulations are largely compatible, major differences existed between U.S. and Mexican regulations concerning drivers’ qualifications, the hours of service, drug and alcohol testing, the condition of vehicles (including their tires, brakes, parts, and accessories), accident monitoring, and the transport of hazardous materials. According to DOT, progress has been made in making truck safety and operating standards compatible, and discussions are still ongoing. NAFTA’s three member nations have accepted the truck inspection standards established by the Commercial Vehicle Safety Alliance (CVSA).For the most part, there are two types of inspections conducted according to the trilaterally accepted truck inspection guidelines—“level-1” and “level-2” inspections. The level-1 inspection is the most rigorous—a full inspection of both the driver and vehicle. The driver inspection includes ensuring that the driver has a valid commercial driver’s license, is medically qualified, and has an updated log showing the hours of service. The level-1 vehicle inspection includes a visual inspection of the tires and of the brakes’ air pressure, among other things, and an undercarriage inspection that covers the brakes, frame, and suspension (see fig. 1). The level-2 inspection, also known as a “walk-around inspection,” includes a driver inspection and a visual inspection of the vehicle. It does not include the careful undercarriage inspection. Trucks that fail inspections for serious safety violations are placed out of service—that is, they are halted until the needed repairs are made. From January 1996 (the first full month of detailed records of inspections) through December 1996 (the most recent month for which data were available as of March 1997), federal and state safety inspectors conducted over 25,000 safety inspections of about 3 million Mexican trucks crossing into the United States. These inspections resulted in an out-of-service rate of about 45 percent for serious safety violations. The monthly out-of-service rates ranged from 39 percent to 50 percent, with no consistent trend (see fig. 2). The average monthly out-of-service rate of 45 percent compares unfavorably with the 28-percent rate for 1.8 million U.S. trucks inspected on the nation’s roads during fiscal year 1995 (the most recent year for which nationwide data are available). However, because inspectors target for inspection vehicles and drivers that appear to have safety deficiencies, their selections are not random. As a result, the out-of-service rates may not necessarily reflect the general condition of all vehicles. In addition, while about half of the 1.8 million inspections of U.S. trucks were level-1 inspections, only slightly more than one-quarter of the inspections of trucks from Mexico were this type. Level-1 inspections are more stringent than level-2 inspections and result in higher out-of-service rates. Consequently, if more of the inspections of trucks from Mexico had been level-1 inspections, the resulting overall out-of-service rate likely would have been somewhat greater than 45 percent. The out-of-service rates for trucks entering the United States from Mexico have also been substantially greater than those for U.S. trucks operating within individual border states (see fig. 3). California’s data show less disparity, which may be because regular inspections since the late 1980s have made Mexican carriers traveling into California more knowledgeable about U.S. truck safety standards. Federal and state truck inspectors we contacted in Arizona, California, and Texas told us that trucks from Mexico are upgrading equipment to improve safety. In their opinion, trucks from Mexico are safer now than they were in late 1995. For example, the inspectors told us that they often find fewer violations per truck, and some previous violations (such as instances of drivers sitting on milk crates rather than secured seats) are now seldom seen. They credit the increased inspections at the border (discussed later in this report) with heightening Mexican carriers’ awareness of and willingness to comply with U.S. truck safety requirements. They commented that the inspections have helped bring about improvements with tires, brakes, and other equipment. Also, many Mexican drivers we spoke to were eager to learn about U.S. safety regulations so they could strive to meet them. Many U.S. and Mexican trucking industry and association officials we contacted said that the relatively high out-of-service rates for trucks from Mexico do not mean that Mexican truck operators will drive unsafe trucks into the United States once access to the remaining portions of the border states and to the United States as a whole is granted. They told us that most trucks currently operating and being inspected at border crossings are used exclusively for short-haul operations and tend to be older trucks that are more likely to have equipment problems leading to out-of-service violations. They believe that Mexican truck operators choosing to operate farther into the United States will use higher-quality trucks because doing so is in their interest. For instance, Mexican trucking companies would not want their trucks to break down or to be taken out of service far from their bases of operations, where repairs would be more difficult and costly, the officials explained. While this reasoning seems plausible, we were unable to obtain information that would confirm or refute it. Most trucks from Mexico enter the United States at 7 of the 23 crossing points for commercial trucks. To provide some assurance that the 12,000 trucks crossing from Mexico into the United States each day will be safe and operated safely, the three border states in our review and DOT have increased enforcement markedly at the major border locations. Although there are 23 locations where northbound trucks from Mexico may enter the United States, about 90 percent of the trucks enter at 7 major crossings—in California (Otay Mesa and Calexico), Arizona (Nogales), and Texas (El Paso, Laredo, McAllen, and Brownsville) (See fig. 4.) Trucks from Mexico enter the United States through the U.S. Customs Service’s ports of entry. Trucks passing through Customs then enter truck inspection facilities where such inspection facilities exist. At locations where separate permanent facilities do not exist, Customs has generally allowed state and federal truck inspectors to carry out their safety inspections on the agency’s property. Permanent facilities allow more rigorous truck inspections to take place, provide scales and measuring devices to screen all trucks for the violations of being overweight or oversize, provide cover to keep inspectors out of the extreme heat prevalent at the border, and signal to the trucking community a permanent commitment to enforcing truck safety standards. In the past year, California opened two permanent truck inspection facilities at its major border crossings, where it aims to inspect and certify the trucks entering the state from Mexico once every 3 months. Texas, with about two-thirds of the truck traffic from Mexico, and Arizona, with about 10 percent of the traffic, have no permanent truck inspection facilities at any of their border locations. Discussions within Texas and Arizona are under way regarding constructing at least one permanent facility in each state. As of January 1997, the three border states in our review had 93 truck inspectors stationed at border crossing locations (see table 1). In addition, DOT approved new temporary positions for 13 truck safety inspectors and, as of January 1997, had 11 of them working at the border. (The 13 positions are for a 2-year term only.) These federal truck inspectors took over for six DOT safety specialists who had been temporarily reassigned to inspect trucks from Mexico at border locations from December 1995 through August 1996. Customarily, DOT does not routinely conduct roadside inspections at fixed locations. Most state truck inspectors (83 of 93) have been stationed at the major border crossing locations. A year earlier, the three border states in our review had 39 inspectors assigned to the major border crossing locations (see table 2). In addition, DOT has assigned its inspectors to each state and then, with one exception, assigned them to the busiest locations within each state.