A California sheriff's deputy who was honored as the department's top officer for two consecutive years has been arrested in connection with an illegal firearms investigation.

The Contra Costa County Sheriff's Office on Friday said they booked deputy sheriff Matthew Buckley, 41, into jail on suspicion of two counts of felony grand theft of a firearm, two counts of receiving stolen property, filing a false report and possession of a controlled substance.

He has been placed on paid administrative leave. 

"When we were first apprised of the allegations, we immediately started an investigation," Contra Costa Sheriff David Livingston said in a statement. "No one is above the law and employees of the Sheriff's Office who violate the law will be held accountable. I am disappointed but this arrest is not a reflection of the many outstanding employees of the Sheriff's Office."

OKLAHOMA SUSPECT IN DEPUTY SHERIFF'S DEATH ALSO FIRED AT A THIRD OFFICER

California sheriff deputy arrested

Contra Costa County Sheriff's deputy Matthew Buckley is charged in connection with an illegal gun case, authorities said Friday.  (Fox San Francisco )

Authorities did not disclose details of the investigation or Buckley's alleged crimes. 

The Contra Costa County Sheriff's union told Fox San Francisco it was aware of the arrest. 

"If he is found guilty he should serve his time," union president Sean Welch, told the news outlet. "It's a complete embarrassment to our association." 

Buckley was also the subject of a 2019 federal lawsuit in which a couple alleged the man was arrested after his girlfriend called 911 to investigate a complaint. 

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