FOND DU LAC, Wis. -

U.S. Rep. Tom Petri has paid nearly $140,000 for legal representation stemming from an ethics investigation he himself requested into his own stock portfolio.

The Fond du Lac Republican asked for the investigation after a media report drew a link between companies that have business before Congress and the amount of stock he owns in those companies.

He asked the House ethics committee to review the matter, and he said he's always been transparent about his stock holdings.

Campaign-finance reports posted this week show that he paid Washington law firm Covington & Burling LLP $137,000 in May and June. The firm is representing him in the probe.

House rules said it's generally permissible for members to use campaign funds to defend themselves in cases that involve the performance of official duties.