Honolulu police Sgt. Daniel Sellers was not in on the alleged mailbox theft conspiracy and is not expected to testify in the upcoming federal criminal trial against retired Police Chief Louis Kealoha, Kealoha’s former deputy prosecutor wife and three other former members of the Honolulu Police Department’s elite Criminal Intelligence Unit, according to details contained in Sellers’ plea agreement.

Sellers was charged with an unlawful search and seizure, lying about it to a federal grand jury and lying to the FBI about watching surveillance video of the alleged staged theft of the Kealohas’ mailbox. All three charges are felonies. He pleaded guilty Friday instead to a misdemeanor for disclosing confidential information to Kealoha’s wife, Katherine Kealoha. Sellers was never charged with conspiracy.

The surveillance video shows a man in a white car taking the Kealohas’ mailbox. Officials have not made public the identity of the person in the white car.

The Kealohas identified Katherine Kealoha’s uncle as the person who stole their mailbox. The uncle did not own a white car at the time of the incident.

According to his plea agreement, the confidential information Sellers disclosed concerns the owner of a white car who was the neighbor of Katherine Kealoha’s uncle.

Sellers said he searched a law enforcement database for friends, relatives and neighbors of the uncle to see whether any of them owned a car matching the one in the surveillance video, then told Katherine Kealoha that the neighbor’s white car is not the one in the video.

His sentence is scheduled for April, in the middle of the mailbox trial. The lead prosecutor did not object when Sellers’ lawyer asked for a sentencing date before the trial.

The government wrote in the plea agreement that Sel­lers has already provided it with substantial assistance.

Sellers’ guilty plea came on the same day some of the other defendants in the mailbox case filed pretrial motions.

The Kealohas want the court to dismiss the indictment against them because the prosecutor solicited grand jury testimony from a witness about the uncle passing a lie detector test and failed to correct false information a grand juror disclosed to another witness.

Both requests will need to be resolved before trial. U.S. District Chief Judge J. Michael Seabright has not yet scheduled them for hearing.

The other defendants are Derek Wayne Hahn, Minh-Hung “Bobby” Nguyen and retired Maj. Gordon Shiraishi.

The Kealohas also want the court to prevent the government from using in trial any statements they made to the Honolulu Ethics Commission. They unsuccessfully sued the commission in 2015 for information about ongoing investigations against them, then sued the city, the commission and its then-Executive Director Charles Totto, and then-investigator Letha DeCaires in 2016 over the investigations.

The state lawsuit is on hold pending the outcome of the federal criminal cases against the Kealohas.

A private law firm working for the city said in legal papers filed in state court last month that the commission turned over all records of investigations against the Kealohas to the FBI and that despite the departures of Totto and DeCaires, the investigations remain open.