A Civil Service Commission hearing panel has upheld the firing of a Denver police officer accused of stomping on the back of a 16-year-old — finding Tuesday that he beat the boy, then lied about it.

Charles Porter had appealed his firing by former Safety Manager Al LaCabe, who concluded he was one of three gang-unit members who beat Juan Vasquez in a north Denver alley.

The three — Porter, Luis Rivera and Cameron Moerman — all denied beating the teen. Days after the incident, Rivera and Moerman told internal-affairs investigators that when Vasquez was on the ground in handcuffs, Porter jumped on his back.

A jury acquitted Porter, who was the only officer charged with a crime.

Porter appealed LaCabe’s decision, and the three-member panel heard his case in November.

In its decision, the panel upheld seven of the violations found by LaCabe but said the city didn’t prove five others.

“This decision is a victory for Denver citizens, who have an absolute right to expect their officers to accurately and honestly report improper conduct of their fellow officers,” said City Attorney Douglas Friednash.

Porter can appeal the decision to the commission or to District Court. In an e-mail, Porter’s lawyer, Nathan Chambers, said he had no comment.

Nick Rogers, president of Denver’s police union, said, “I accept their decision, and I respect the due process our officers receive.”

The hearing officers who contract with the commission to hear such cases found that the city’s lawyers showed Porter “was complicit with others in committing the act of assault.”

They also showed that Porter used excessive force and committed a deceptive act by omitting information regarding “the use of unlawful force against Juan Vasquez,” according to the 18-page decision.

Among other things, the city didn’t prove that Porter committed first-degree assault, according to the decision. The panel thought that Moerman and Rivera were not credible witnesses, that there was no proof Porter intended to cause bodily injury and that medical evidence as to the cause of the injuries was questionable.

The incident was among a spate of cases alleging brutality by Denver police officers that came to public attention over the past few years. During Porter’s hearing, LaCabe and retired Division Chief Daniel O’Hayre said the culture of the department is tolerant of excessive force but that few officers engage in it.

Vasquez couldn’t be reached for comment. His liver was lacerated and his kidneys damaged in the arrest, and the city eventually paid $885,000 to settle a lawsuit in the case.

Vasquez, who was wanted for vehicle theft and failing to report to a probation officer, was drinking with a friend on the night of April 18, 2008, when he saw a police car approaching and ran. The cops ran him down in an alley near 37th Avenue and Osage Street.

Tom McGhee: 303-954-1671 or tmcghee@denverpost.com