Republican Congressman Devin Nunes of California has filed a lawsuit claiming a left-leaning transparency nonprofit conspired with a research firm to damage his reputation.

The lawsuit in federal court in Alexandria follows two that Nunes filed in state court against parody Twitter accounts, Twitter, a Republican strategist and the media company McClatchy for reporting on or mocking him.

In the federal suit, Nunes says ethics complaints filed by the Campaign for Accountability are retaliation for his work on the House Intelligence Committee, in which he has repeatedly impugned the integrity of the firm Fusion GPS and the credibility of a dossier a researcher hired by the firm compiled on President Trump’s alleged connections to Russia.

Nunes and other conservatives have longed seized on the dossier as evidence of bias in the Russia investigation, because Fusion GPS’s research was initially funded by Hillary Clinton’s campaign. While the FBI was aware of that work, it was not the basis for its probe into Russian election influence or the special counsel investigation headed by Robert S. Mueller III.

CfA has filed three ethics complaints against Nunes: one alleging the congressman failed to list business interests on his financial disclosure forms and two accusing him of leaking confidential information to the press.

In the suit, Nunes denies sharing text messages sent by Sen. Mark R. Warner (D-Va.) with Fox News, a leak that provoked concern about his committee from senators on both sides of the aisle.

The lawsuit claims “active, coordinated and ongoing corruption, fraud and obstruction of justice” that caused “injury to his business and reputation, court costs, and other damages.”

Nunes highlights a $138,684 payment from CfA to Fusion GPS for research last year. The nonprofit told the Daily Caller that Fusion was not hired to investigate Nunes.

Both Fusion GPS founder Glenn Simpson and a spokesman for the Campaign for Accountability did not immediately return a request for comment Wednesday night.