The Eighth U.S. Circuit Court of Appeals agreed with a district-court decision Monday, rejecting a suit by a Minneapolis police officer who accused the department and former Chief Tim Dolan of trying to silence him for denouncing police misconduct.

Sgt. Michael Keefe, now in the 1st Precinct, sued after he was removed as head of the department's Violent Offender Task Force, suspended and demoted from lieutenant.

Even if some of Keefe's accusations were true, they did not rise to the level of malice or "inhumane abuse of official power," a three-judge panel ruled.

The ruling said Keefe's own actions supported the discipline.

"Indeed, Keefe admitted to placing an anonymous call to Chief Dolan's wife and to failing to carry his firearm and badge for several months," the panel said.

In addition, it said, the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) banned Keefe from their offices. "These bans were relied upon as part of the basis for Keefe's demotion."

In an interview Monday, Keefe said the FBI banned him after he refused to be interviewed. He said the ATF lifted its ban and gave him an award.

Keefe, who is white, had questioned an internal investigation of six Minneapolis police officers, four of them black, after a gang leader claimed they were corrupt.

After Keefe confronted the gang leader, the FBI said he'd harmed the inquiry and asked Dolan to take him off the case.

Keefe made an anonymous phone call to Dolan's house and told his wife the FBI was corrupt and blackmailing an officer, the appeals court said. He later admitted to making the call. He said he had not carried a gun or badge for several months while serving as an officer because he was afraid of being framed and shot.

Now that his case is closed, Keefe said he hopes the Justice Department will call a grand jury. He said his case has turned up details in which police have turned on police, FBI agents and assistant U.S. attorneys. "This is a massive case of corruption," he said.

Minneapolis City Attorney Susan Segal said she was pleased with the Eighth Circuit decision.

"Everything he has alleged has been extensively reviewed without any evidence there is any basis for his claims," she said.