A Maui police sergeant says he took part in a scheme with another officer and a third person to bribe a witness who accused the other officer of stealing $1,800 from him.

Walter “Kepa” Ahuna, 35, pleaded guilty in U.S. District Court on Wednesday to one count of conspiracy to commit witness tampering. He faces a maximum 20-year prison term at sentencing in November.

Ahuna remains free on $25,000 unsecured signature bond. As of Wednesday, Ahuna was still employed by the Maui Police Department but faces a likely administrative investigation.

The other two people with whom Ahuna admits he conspired are Anthony Maldonado and Damien K. Kaina Jr. Ahuna’s federal court record identifies Maldonado and Kaina by their initials A.M. and D.K.

Assistant U.S. Attorney Jill Otake said in court Wednesday that on Sept. 30, 2015, Maldonado stole money from a motorist at a traffic stop. The motorist reported the alleged theft to Maui police, who arrested Maldonado then released him pending further investigation. The federal court record says Maldonado stole $1,800.

Following his arrest, Maldonado met with Ahuna and Kaina and told them his wife had received some money that could be used to bribe the motorist to withdraw the complaint, Otake said. Their plan was to persuade the motorist to tell police that he found the missing $1,800. When Ahuna warned them that the plan was against the law, Kaina offered to take the blame and say it was his idea, Otake said.

She said Kaina went to the motorist’s home on Oct. 13, 2015, and handed over money.

Maui police arrested Maldonado and Kaina two days later. Maldonado was released but placed on administrative leave without pay. County officials say he was fired last year. He has not been charged.

The county prosecutor charged Kaina in November 2015 with bribing a witness, then two weeks later told the court the case is pending further investigation and dropped the charge.