Congressman Mike Coffman has asked a judge to stop a public hearing next month to determine whether he violated ethics rules as secretary of state.

Coffman's lawyer, Doug Friednash, filed court documents Wednesday asking a Denver district judge to block proceedings by the new state Independent Ethics Commission, which scheduled a March 6 hearing on a complaint filed a year ago by Colorado Ethics Watch.

The government watchdog group accuses Coffman of breaking ethics rules while serving as secretary of state by allowing an employee of the elections division, which is part of the state agency, to operate a partisan political business.

Ethics Watch also alleges that Coffman approved electronic voting machines made by a company that hired a lobbying group he used to run his successful congressional campaign.

Coffman, a Republican who represents the 6th Congressional District, said his lawyers advised him not to comment.

He has previously denied wrongdoing and has accused Ethics Watch of targeting only Republicans and seeking to harass him.

The ethics commission was formed last year as a result of Amendment 41, a state law approved by voters in 2006.

The five-member panel is charged with handling ethics complaints filed against public officials.

Coffman and his lawyers have argued unsuccessfully to the commission that the Ethics Watch complaint was frivolous and should be dismissed on a number of grounds. Friednash repeated those arguments in court filings this week.

Friednash also expressed concern about damaging Coffman's reputation.

"The irreparable injury from the commission's . . . proceedings against Mr. Coffman is obvious and great," Friednash wrote. "There is a great danger that the stigma of a pending ethics complaint and its subsequent investigation subjects a public official to the immediate distraction from public service; public suspicion, scorn, and humiliation; the loss of public support; and other emotional stress."

Jane Feldman, executive director of the commission, declined to comment. The commission has roughly two weeks to respond in court.

The complaint against Coffman is the only one of six filed since the commission was established that is moving forward. The others were dismissed on procedural grounds.

Chantell Taylor, executive director of Ethics Watch, called the court motion "a clear indication that former Secretary Coffman will try anything to avoid accountability."