SPECIAL REPORT: Data flawed on Mexican truck safety reg compliance

| 9/30/2008

Tuesday, Sept. 30, 2008 – A study touting a 90 percent compliance rate by Mexican motor carriers with U.S. safety regs has been debunked by a report released by the Department of Transportation Office of Inspector General.

The report, released Sept. 24, outlined Inspector General Calvin Scovel’s criticism of the “scope and methodology” of the Federal Motor Carrier Safety Administration review of Canadian and Mexican trucks’ compliance with U.S. safety regs.

The Inspector General’s office reviewed a report submitted by FMCSA officials to Congress in April 2007. That report relied heavily on inspections conducted at the U.S.-Mexico border by the Texas Transportation Institute. The school conducted the inspections as part of a study funded by an FMCSA grant.

The integrity of the statistics provided was challenged by the Inspector General’s office on a couple of different fronts.

First, the way TTI selected the border crossings where inspections took place and the trucks chosen for inspection was not random.

“Neither the border crossings nor the vehicles sampled were chosen at random, and therefore the results are biased,” the IG report stated.

TTI then used mathematical probability formulas to estimate the overall compliance with U.S. safety regs by Mexican motor carriers. The Inspector General’s office said in its report that the wrong formulas were used – leading to incorrect statistical estimates of safety compliance.

In addition to challenging the mathematical process and the final statistics, the Inspector General called into question TTI’s assumption that trucks manufactured in Mexico since 1996 were automatically compliant with U.S. safety regs.

“This assumption was based on FMCSA’s analysis of Mexican manufacturing practices, which concluded that ‘most’ model year 1996 and later Mexican-manufactured commercial motor vehicles ‘may’ meet FMVSS,” the IG report stated.

Responses to the Inspector General’s findings from both TTI and FMCSA officials were included in the report.

Officials with TTI agreed that the way border crossings and trucks were chosen was “potentially compromised.” But they contend that the results were not affected. Further defending their research, TTI officials claim they used the right mathematical formulas to arrive at their final statistics.

FMCSA officials acknowledged that concerns raised about the sampling methods may be valid, but they don’t think that the final stat of 90 percent compliance would be significantly affected.

On the flip side, FMCSA officials did concede that the mathematical formulas used by TTI should have been reviewed by FMCSA staffers instead of just signed off on.

– By Jami Jones, senior editor