According to an audit report from the Office of Inspector General the number of participants enrolled in the cross border trucking pilot program between Mexico and the US was too low and therefore did not represent an adequate statistical sample
To prevent truck accidents and keep the roads safe between Mexico and the US, Congress prohibited the FMCSA to allow long-haul cross-border transportation of cargo and passengers between Mexico and the USA – as provided for in the NAFTA agreement in 1992 – until certain safety requirements were met and a pilot program for granting long-haul authority to Mexico-domiciled motor carriers has evaluated the potential impact on safety.
The pilot program was recently completed by the FMCSA. A recent audit of this pilot program by the Office of Inspector General found that even though the pilot was well run and followed all necessary steps and conditions, it lacked an adequate number of Mexico-domiciled carriers to yield statistically valid findings.
The complete audit report can be downloaded here