S.F. sheriff’s deputy arrested in assault on hospital patient

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A San Francisco sheriff’s deputy was out on bail Saturday after being take into custody for allegedly choking a hospital patient and then arresting the man for trying to assault him with his cane, authorities said.

Michael Lewelling, 33, was arrested Friday and charged with perjury, filing a false police report, filing a false instrument and assault under the color of authority — all felonies — as well as misdemeanor battery for the Nov. 3 attack at San Francisco General Hospital, according to the district attorney’s office.

Lewelling was assigned to the Sheriff’s Department’s patrol unit at the hospital when he filed a report accusing the victim of attempting to attack him with a wooden cane. The man was arrested in connection with various felony and misdemeanor offenses.

The district attorney’s office declined to file charges and the man was released the next day. Prosecutors requested video evidence, which allegedly showed Lewelling instigating the attack.

Prosecutors said the victim had been sleeping in a chair in the emergency room’s waiting area about 5 a.m., and that the video showed Lewelling approaching the man, engaging him in conversation as he woke up.

When the victim tried to walk away with the help of his cane, the video showed, Lewelling grabbed the back of his collar, shoving him back into the seat and knocking his cane away, the district attorney’s office said.

The video then showed Lewelling grabbing the man’s throat and choking him before placing him under arrest, prosecutors said.

“The fact that a sheriff’s deputy allegedly battered a patient at San Francisco General Hospital is unnerving,” District Attorney George Gascón said in a statement. “What’s worse is that he’s also alleged to have perjured himself on a police report, unforgivable conduct that led to the arrest of the innocent victim.”

The Sheriff’s Department said an arrest warrant for Lewelling was issued after six weeks of investigation by the department’s criminal investigation unit.

“The San Francisco Sheriff’s Department places paramount value in maintaining the public trust bestowed upon peace officers,” the department said in a statement. “To that end, the San Francisco Sheriff’s Department is committed to holding its employees accountable for their conduct.”

Lewelling has worked for the department since August 2009, said Senior Deputy Enrique Luquin. He had been assigned to the patrol unit at the hospital since December 2013.

Lewelling surrendered and was booked into County Jail about 6:15 p.m. Friday. He later was released on $138,000 bail.

Vivian Ho is a San Francisco Chronicle staff writer. E-mail: vho@sfchronicle.com Twitter: @VivianHo