GOP Rep. Nancy Mace is under investigation by the House Ethics Committee for allegedly attempting to profit off of a congressional program intended to defray housing costs for lawmakers’ Washington, DC, residences — a claim she has denied.

According to a newly published report from the Office of Congressional Conduct, the South Carolina Republican sought and was paid roughly $9,500 beyond the actual costs of her residence in DC.

“There is substantial reason to believe that Rep. Mace engaged in improper reimbursement practices,” the nonpartisan watchdog group said in its official referral to the House Ethics Committee. The ethics committee announced Monday it is investigating the matter.

Mace was participating in a housing reimbursement program for members of Congress, which is intended to help subsidize lodging, food and travel expenses for lawmakers who must maintain households both in Washington and in their districts. The program has drawn intense scrutiny, since it does not require detailed expenses and has effectively given lawmakers who take part a major pay bump.

Mace did not respond to inquiries from the Office of Congressional Conduct, according to the report.

But a lawyer for Mace, William Sullivan, fiercely disputed the claims in a letter to the House ethics panel, calling the report “fundamentally flawed.”

The report’s narrative, Sullivan suggested, appeared to be “influenced by Rep. Mace’s former fiancé,” who co-owned the home with her.

Mace is not seeking reelection to the House and is running in a competitive GOP primary to become South Carolina’s next governor.

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