CHICAGO (STMW) — The former deputy police chief of south suburban Midlothian faces up to 10 years in prison after he was convicted of using excessive force for beating a “Black Wednesday” drinker with his police baton.

Steve Zamiar, 47, frowned, dropped his head and closed his eyes as a federal jury returned its guilty verdict Friday morning.

Jurors deliberated for just two hours at the end of the three-day trial before deciding that Zamiar acted unreasonably when he repeatedly beat 31-year-old James Snyder in the back and head with a steel baton in the early hours of Thanksgiving 2011.

They may have been swayed by the testimony of Sgt. Edmond Olmos, who took the highly unusual step of testifying against a superior officer when he gave eye-witness testimony backing Snyder’s claim that Zamiar’s attack in the parking lot of Durbin’s bar was unprovoked.

The verdict stunned Zamiar’s family, which showed its support throughout the trial. Several relatives gasped as the verdict was announced and Zamiar’s attorney Ralph Meczyk said he was “shocked.”

Zamiar’s defense team was frustrated during the trial that it could not introduce evidence of Snyder’s past run-ins with the police, or the fact that he twice went to the Horseshoe Casino to play poker before he finally sought treatment for what he claimed were excruciating injuries inflicted by Zamiar.

U.S. Attorney Zach Fardon — who watched Zamiar’s testimony on Thursday and took a close interest in the case — was also in the courtroom as the verdict was announced, but showed no reaction.

Just a week ago Fardon hosted U.S. Attorney General Eric Holder at a “round-table” discussion about police-community relations in the wake of the outrage over the deaths at police hands of black men Michael Brown and Eric Garner.

Though Zamiar’s case lacked the incendiary racial component of those cases — both he and Snyder are white — U.S. District Judge Sharon Johnson Coleman quizzed jurors before the trial about their opinions on police brutality to weed out any bias.

Zamiar had claimed that Snyder had squared up to him in a “fighting stance” and was throwing a punch when Zamiar hit him in self-defense.

He was fired by Midlothian last year, following his indictment.Friday’s verdict leaves unresolved a second federal criminal charge against Zamiar, who is also accused of an unprovoked 2010 attack on a detainee.

That case was due to go to trial in January, but has now been postponed. Zamiar — who has been sued five times in federal court for alleged brutality — also faces a civil lawsuit brought by Snyder.

But Coleman, at least, allowed him one small mercy: Christmas at home with his family.

Though federal law calls for defendants convicted of crimes of violence to be immediately taken into custody in all but extraordinary circumstances, Coleman gave Zamiar’s lawyers until April to challenge his detention.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)