The issue of Mexican motor carriers operating across the U.S. border is not over, at least not in the eyes of the International Brotherhood of Teamsters.

The union announced today that it has filed suit with U.S. Court of Appeals for the Ninth Circuit to block the Department of Transportation from implementing its decision to open the U.S. border to Mexico-based motor carriers later this year.

The Teamsters said that the lawsuit “contends that the DOT's final report to Congress violated the Administrative Procedures Act because its conclusion— that Mexico-domiciled carriers operate at a level of safety equal to or greater than U.S. and Canadian carriers— is arbitrary and capricious in light of the admitted lack of significant data from a pilot program Congress required DOT to conduct.”

Joining the union in the suit Advocates for Highway and Auto Safety and the Truck Safety Coalition.

According to the Teamsters, DOT opted to open the border to Mexico-domiciled trucks “despite the DOT Inspector General (IG) issuing a report which acknowledged that it had been unable to develop statistically significant data in the pilot program.”

 "It is disappointing that the DOT has chosen to ignore the findings of the Inspector General and is moving forward with opening the border to Mexican trucks,” said Teamsters general president Jim Hoffa. “The Teamsters Union will continue to fight for highway safety; the safety of our roads cannot be compromised based on this failed program."

 The union noted that in a letter to United States Trade Representative Michael Froman last week, Hoffa called for the Obama Administration “to protect highway safety and reopen negotiations over Mexican cross-border trucking as part of the ongoing Trans Pacific Partnership."