SPRINGFIELD, Ill. (AP) —A Chicago lawyer who donated $500 to former U.S. Rep. Aaron Schock’s campaign is suing for reimbursement following his resignation in March amid accusations of fraud and improper enrichment.

Howard Foster filed a lawsuit Wednesday in the U.S. District Court in Chicago seeking repayment of all contributions to Schock’s campaign. Foster wants to make it a class-action suit although he is currently the only plaintiff.

The Justice Department is investigating the 33-year-old Schock’s congressional expenses and business deals following reports of lavish spending and improper mileage reimbursement.

The lawsuit says Foster donated to Schock because he thought he “was ethical, (and) a breath of fresh air,” but that Schock instead engaged in “political sleaze for personal gain.”

A Schock spokesman declined comment.

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