A retired Murray police detective is facing an assault charge for allegedly striking a suspect during an arrest.

Luis Alberto Argueta-Salazar was charged in July with misdemeanor assault, but city prosecutors had kept the charging documents secret until last week.

Allegations became public in a motion filed in a separate case where Argueta-Salazar had been one of several law enforcement officers to testify about investigating a nurse who had been accused of multiple sexual assaults at Salt Lake County hospitals.

Prosecutors with the attorney general’s office asked ahead of that trial that the defense not be allowed to question Argueta-Salazar about his pending case.

The prosecutor wrote in a motion that Argueta-Salazar described the suspect as an “inebriated individual” who had become “combative.”

The officer described the strike as being in self-defense — but after an investigation by South Jordan Police Department, Argueta-Salazar was charged with a class B misdemeanor in Murray’s justice court.

Prosecutors initially filed charges under seal, but a public version was filed last week after The Salt Lake Tribune inquired about the case with Utah courts officials.

The filing offers no details about the allegation against Argueta-Salazar, listing only the legal definition of assault. It lists the offense date as June 13 and location as near 4500 S. State St.

Neither city prosecutors nor Argueta-Salazar’s attorney immediately responded to requests for comment Tuesday.

Argueta-Salazar pleaded not guilty to the charge last week, and a trial is scheduled for January.

He testified last week in the nurse’s trial that he has been with the Murray police force since 1994 and retired last month.