Republican lawmakers are demanding the Environmental Protection Agency (EPA) inspector general’s office investigate alleged collusion between agency officials and lobbyists to undermine the Trump administration’s deregulatory agenda.

Four GOP lawmakers and the chair of a powerful House subcommittee want to know why EPA officials worked with trucking lobbyists on a study that was never approved by administration officials, yet obtained and touted by opponents of repealing regulations on refurbished heavy-duty truck engines.

“When EPA Administrator Scott Pruitt repealed the current glider rule, career employees at the EPA communicated with the original equipment manufacturer (OEM) with the intent of eliminating the glider industry,” four GOP lawmakers, led by Rep. Bill Posey of Florida, wrote to EPA Inspector General Arthur Elkins.

“In our opinion, EPA’s conduct undermines the current Administration’s policies and prevents the repeal of the rule,” Republicans wrote to Elkins in a letter sent Thursday that was obtained by The Daily Caller News Foundation.

Separately, Rep. Greg Gianforte, chairman of a subcommittee on the House Committee on Oversight and Government Reform, sent a letter to Elkins demanding an investigation into whether collusion between EPA and Volvo lobbyists “violated any policies or procedures intended to ensure objectivity and integrity of tests conducted at” the National Vehicle and Fuel Emissions Laboratory (NVFEL) in Ann Arbor, Mich.

Glider kits are new truck bodies that use refurbished engines and are substantially cheaper to buy than trucks with new engines.

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