Gene Stilp wanted the state Ethics Commission to investigate whether House leaders used $290,000 in state money for political polls. Instead, Mr. Stilp is the one who wound up under investigation.

While the commission dismissed his complaint against former state House Majority Leader Bill DeWeese, it fined Mr. Stilp $500 last year for publicly discussing his filing with newspaper reporters.

Aiming to ensure that doesn't happen again to him or anyone else, Mr. Stilp Friday filed suit against the commission in U.S. District Court in Harrisburg. He claims the commission's regulation unconstitutionally violates his right to free speech.

"It's very, very chilling. It makes people afraid to file a complaint," said Mr. Stilp, founder of the activist group Taxpayers and Ratepayers United.

Ethics regulations prohibit filers from discussing active complaints, with a few exceptions.

Mr. Stilp distributed news releases to reporters before filing his complaint, but did not discuss the complaint once it was before the commission.