A federal appeals court panel on Tuesday upheld the conviction of former Spokane police Officer Karl Thompson.

The three judges denied claims by Thompson’s attorneys that courtroom errors following the 2006 beating death of Otto Zehm justified sending the case back for a new trial.

Thompson is serving a four-year sentence at a minimum-security facility in Safford, Arizona, after a jury in Yakima found him guilty in 2011 of using excessive force and attempting to conceal evidence in Zehm’s death.

The fatal beating prompted a lengthy legal review that ended with the two guilty verdicts. Thompson’s attorneys said that prior to the trial prosecutors did not provide the defense team statements made by a key witness, forensics expert Grant Fredericks, that movement seen in a surveillance video of the beating could have been baton strikes or some other motion.

Zehm, a 36-year-old janitor, died after a confrontation with Thompson and other police officers inside a north Spokane convenience store on March 18, 2006.

Witnesses reported seeing Thompson strike Zehm multiple times with a baton, shoot him with a stun gun and hog-tie him after he responded to a call of a possible theft near a Spokane Zip Trip store. Zehm was holding a 2-liter bottle of cola. After being taken to a hospital, Zehm lost consciousness and died a few days later.

The panel reviewed four issues raised by Thompson’s attorney Carl Oreskovich: that the trial judge prevented testimony by Fredericks that would have helped his case; that testimony about Zehm not fleeing or hiding from police undermined Thompson’s claim that Zehm might have used the soda bottle as a weapon; that the court gave the jury flawed instructions; and that juror misconduct occurred during the trial that should have led to a mistrial.

In the appeal, Oreskovich said he and others on Thompson’s defense team were misled by pretrial statements about the conclusions Fredericks would make from a surveillance video of the incident.

Oreskovich said he was led to believe some of Fredericks’ statements were beneficial to prosecutors when in fact they were beneficial to Thompson.

The appeals court panel, however, noted that Fredericks did not testify during the trial.

The court ruling said: “Further, the government’s pretrial disclosures put Thompson on notice of potentially favorable opinions in Fredericks’ reports; Thompson was thus not deprived of the opportunity to develop a defense strategy that utilized those opinions. Finally, the nondisclosure did not impede Thompson’s ability to cross-examine the government’s witnesses.”

Oreskovich said he will consider seeking a full review of the decision by the 9th Circuit Court of Appeals.

Because a magistrate ruled that Thompson is indigent, his attorneys have been paid $564,000 so far from a federal defense fund. That sum is only for legal efforts before and during the Yakima trial.

Costs associated with Thompson’s appeal will not be published by the 9th U.S. Circuit Court of Appeals until the case is concluded, a spokesman said.

The use of taxpayer money for such cases is authorized by the federal Criminal Justice Act, passed by Congress to provide reliable legal defense for lower-income defendants.