Republican lawmakers are launching an investigation into claims that the Environmental Protection Agency, while giving preferential treatment to environmental groups, made it harder for conservative groups to obtain government records.

“According to documents obtained by the Committees, EPA readily granted FOIA fee waivers for environmental allies, effectively subsidizing them, while denying fee waivers and making the FOIA process more difficult for states and conservative groups,” wrote Republican lawmakers, including Rep. Darrell Issa and Sens. David Vitter, Chuck Grassley and Jim Inhofe in a letter to the EPA.

Citing a report by The Daily Caller News Foundation, Republicans are asking the EPA to hand over all Freedom of Information Act fee waiver requests, responses to requests, and FOIA officer training materials since the beginning of the Obama administration.

Lawmakers are also asking for all communications regarding FOIA fee waiver requests or appeals under the Obama administration.

The free-market Competitive Enterprise Institute obtained documents showing that since January 2012, the EPA granted fee waivers for 75 out of 82 FOIA requests from major environmental groups and only denied seven of them, giving green groups a 92 percent success rate.

At the same time, the EPA rejected or ignored 21 out of 26 fee waiver requests from conservative groups.

“The startling disparity in treatment strongly suggests EPA’s actions are possibly part of a broader effort to collude with groups that share the agency’s political agenda and discriminate against states and conservative organizations,” the lawmakers wrote. “This is a clear abuse of discretion.”

Republicans are tying the EPA to the broader controversy over the Internal Revenue Service targeting conservative groups.

“We know the Obama EPA has completely mismanaged FOIA, but granting fee waivers for their friends in the far-left environmental community, while simultaneously blocking conservative leaning groups from gaining access to information is really no different than the IRS disaster,” said Vitter.

Acting EPA administrator Bob Perciasepe announced Thursday that he was asking the inspector general to look into the matter.

“I am going to get an independent look at all that information so I can get a determination,” said Perciasepe, adding that the agency’s shift to an online system often means that groups are not charged any fees even if they are not formally waived.

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