Rep. Steve Stockman (R-TX) may have violated federal law and House rules when he accepted campaign donations from two of his congressional staffers, the Office of Congressional Ethics (OCE) said Wednesday.

OCE announced in a press release that it had sent a referral in March to the House Ethics Committee recommending further investigate a number of allegations, including that Stockman made false statements and “endeavored to impede” OCE’s investigation.

According to OCE, Stockman accepted campaign contributions from two congressional staff members in February 2013. The campaign’s subsequent campaign finance reports identified the donors as family members of the employees. Stockman also allegedly was paying those two staff members full-time salaries when they were only doing part-time work.

Earlier this year, Stockman lost a longshot primary challenge to Sen. John Cornyn (R-TX). He has announced that he won’t seek reelection in the fall, and in April he disclosed that he was facing an ethics probe, though he chalked it up to an “FEC reporting error.”

“My office is aware of and is cooperating fully with the Ethics Committee’s preliminary inquiry into an FEC reporting error,” Stockman said at the time. “I thus join 34 of my colleagues who have also been the subject of an [Office of Congressional Ethics] review in the 113th Congress, and am confident the Ethics Committee will ultimately dismiss the matter after it completes a careful review.”

On Wednesday, the House Ethics Committee issued a statement acknowledging that it had received OCE’s referral.