MARTINEZ — A former Contra Costa County Sheriff’s deputy who allegedly stole an Antioch man’s firearm and kept judges’ e-signatures in his patrol car without permission pleaded no contest to three felonies in a plea deal that allows him to avoid incarceration.
Matthew Allen Buckley, 42, pleaded no contest to possession of an illegal assault weapon, filing a false police report and preparing false documentary evidence. The terms of the deal, finalized Wednesday, say Buckley will receive a prison sentence of three years and eight months with a major caveat: he can avoid actually going to prison if he completes a six-month drug rehabilitation program.
Buckley was charged in February 2023 with six felonies and one misdemeanor in an investigation that started when the relative of a deceased man whose firearms had been seized by police made several attempts to recover the guns, but became suspicious when Buckley appeared to be giving him the run-around. The Contra Costa Sheriff’s Office launched an investigation and found an AR-15 — along with two grams of methamphetamine — in Buckley’s Pinole home, according to police testimony.
Buckley was also found in possession of a thumb drive containing e-signatures of Contra Costa County judges, potentially giving any officer who possessed them the power to sign and serve fraudulent search warrants. A news release by the Contra Costa District Attorney’s Office says authorities found “Buckley created false documents and signed for a judge without his consent on multiple search warrant returns for unrelated cases.”
In one case, Buckley falsely claimed to have booked two guns into evidence, but actually disconnected the lower sections of the guns and kept them for himself, prosecutors said. His attorney didn’t immediately respond to a request for comment.
At Buckley’s July 2023 preliminary hearing, a sheriff’s investigator testified about another suspicious interaction between Buckley and a sergeant, who reported that during a training exercise, Buckley presented her with a form she’d never seen before, yet contained her signature. When she demanded an explanation, Buckley allegedly responded, “It’s fine, you know about it, so it’s all good.”
At the time of his arrest, Buckley was a 15-year veteran of the sheriff’s office who was well-respected by peers. He was named the agency’s “Officer of the Year” in 2019.
Years ago, he also worked as a bailiff for Contra Costa District Attorney Diana Becton, who previously served as a county superior court judge. Becton attempted to recuse her office from the prosecution but the California Attorney General passed it back to the Contra Costa DA’s Office, after telling Becton to simply wall herself off from the case, multiple law enforcement sources said.
