Pursuant to a congressional request, GAO reviewed whether commercial passenger vehicles entering the United States from Mexico are meeting U.S. safety standards, focusing on: (1) the number and types of commercial passenger vehicles entering U.S. border states from Mexico; and (2) actions taken by the Federal Highway Administration (FHwA) and U.S. border states to provide safety inspections for commercial passenger vehicles arriving at the U.S.-Mexico border.

GAO noted that: (1) according to the U.S. Customs Service, there were about 218,000 commercial passenger vehicle crossings from Mexico to the United States, a daily average of 598 crossings, from June 1996 through May 1997, the latest data available; (2) about 85 percent of these crossings occurred at four crossing points, two in California and two in Texas; (3) while Customs records the number of vehicle crossings from Mexico into the United States, many of these vehicles may cross the border several times a day (e.g., airport shuttles) and each crossing is included in Customs' vehicle crossing count; (4) furthermore, Customs does not record the identity of individual vehicles, the type of vehicle (e.g., motor coaches or vans), or whether the vehicle is owned by either a U.S. or Mexican carrier; (5) as a result, no reliable information exists either on the actual number of Mexican-owned commercial passenger vehicles that enter the United States or on how many of each type of vehicle enters the country--information needed to assess the extent to which these vehicles are safe and are operated safely; (6) FHwA and state inspectors have carried out few safety inspections of commercial passenger vehicles entering the United States from Mexico primarily because their emphasis has been on inspecting commercial trucks; (7) FHwA inspectors in Texas and state inspectors in California conducted border safety inspections of 528 commercial passenger vehicles from January through May 1997 out of an estimated 90,000 crossings; (8) about 22 percent of these commercial passenger vehicles were placed out of service for serious safety violations, such as steering or brake problems; (9) FHwA inspectors in California and state inspectors in Texas had not conducted any inspections as of May 1997; and (10) the dearth of safety inspections, coupled with insufficient information on the number and kinds of Mexican-owned commercial passenger vehicles entering the United States, precludes any assessment of whether these commercial passenger vehicles are safe and are being operated safely.