Updated

A former Omaha police office charged with assault in the death of a mentally ill man he's accused of shocking a dozen times with a stun gun turned himself in before a court hearing Friday and was expected to post bail later in the day.

Scotty Payne wore a yellow jail jumpsuit during his appearance in a jailhouse courtroom for his first hearing on the second-degree felony assault charge. He'd turned himself in to authorities hours earlier as arranged by officials and Payne's attorneys.

Bond was set at $25,000 and Payne's attorneys said he would post the 10 percent required for him to be released later Friday. Payne's preliminary hearing was set for Sept. 11. He faces up to 20 years in prison if convicted.

Payne and former officer Ryan McClarty were charged earlier this week in a June 5 altercation that led to the death of Zachary Bearheels, 29, at an Omaha convenience store.

Police cruiser video shows Payne using a stun gun on Bearheels and McClarty dragging Bearheels by his hair and repeatedly punching him in the face. McClarty has been ticketed for misdemeanor assault in the case.

Prosecutors have said Payne shocked Bearheels 12 times, but his attorneys say officials came up with that number after an audit of the officer's Taser showed it was activated 12 times during the encounter. Defense attorney Steve Lefler said Friday that he doesn't know whether the stun gun's probes made sufficient contact with Bearheels, bringing into question whether the man was shocked 12 times.

Two Omaha police unions have criticized the charges, saying Bearheels was combative when the officers tried to take him into custody. Lefler agreed, saying Payne used what he believed to be non-lethal force to try to get Bearheels under control.

"I mean, what's the next step? You pull out your gun?" Lefler asked following Friday's hearing. "Just because someone is mentally ill doesn't mean that they're not a risk to the public."

But prosecutors say the use of the stun gun was excessive, saying Bearheels had committed no crime and that Payne at one point held the trigger of the stun gun, shocking Bearheels for 18 seconds.