DENVER -- A gun-rights activist was not covered by the Constitution's guarantee of free speech when he threatened to have a militia arrest two judges, the Colorado Court of Appeals ruled Thursday.

Rick Stanley was convicted of attempting to influence a public official after he wrote the judges, threatening they would be arrested for treason by the "Mutual Defense Pact Militia" if they did not overturn his previous conviction on a weapons charge.

Stanley appealed, arguing his threats were protected by the First Amendment because they were not "true threats," or serious statements of intent to commit violence.

A three-judge panel of the appeals court disagreed. "The statements at issue here threaten violence," the panel said, noting that treason is punishable by death.

The panel said the First Amendment does not allow people to express serious intent to commit violence.

"We reject defendant's contention that his statements necessarily contained mere `criticism' of the judges," the panel said.

Thornton Municipal Judge Charles Rose, who had sentenced Stanley to 90 days in jail in 2002 for carrying a loaded gun onto public property, had testified Stanley's letter made him "afraid for his life," the appeals panel said.

Adams County District Judge Donald Marshall Jr., who upheld the weapons conviction and sentence, testified he considered Stanley's letter alarming and a direct personal threat.

Stanley's conviction on the weapons charge stemmed from a 2001 incident in which he took a loaded gun to political rally when he was running for the U.S. Senate as a Libertarian. The arrest took place in Veteran's Park, just across the street from the State Capitol.

Stanley was arrested in 2002 for carrying a loaded .357 pistol on his hip in Thornton, Colo., at the Harvest Festival, in violation of that city's ordinance against concealed weapons.

Stanley was convicted in June 2004 of two counts of attempting to influence a public official, a felony, for sending the letters to the judges. He was sentenced to six years in prison and was ordered to pay $10,000 in fines and $8,250 in restitution for the cost of overtime for police hired to protect the judges.

It was not immediately clear whether Stanley had begun serving his sentence or would appeal. His attorneys did not immediately return a call.