UPDATED at 5:30 p.m. with more detail.

EDWARDSVILLE • Brian Pinkas is on trial here this week after an unusual gamble that could get him out of prison if he wins — or more than double his sentence if he loses.

Pinkas, 51, does not dispute that he killed his girlfriend with a shotgun in Granite City in 2004. But he says it was an accident.

He tried for years to withdraw his guilty plea to a first-degree murder charge, so he could get a chance to make his case to a Madison County jury.

In 2005, Pinkas argued that his lawyer had been ineffective, that he had been under the influence of alcohol when he confessed and that he was affected by psychotropic drugs when he made his plea.

When none of that worked, he resorted to a surprising claim — that he was not given a stiff enough prison sentence.

On that point, Illinois’ 5th District Appellate Court agreed.

In the wording of their 2011 order, the appeals judges seemed to acknowledge his peril in bringing it up. They said they were remanding the case to the trial court “so that he can withdraw his guilty plea and have his conviction and sentence vacated, if he so desires.” The order warns that he would not only be liable to prosecution all over again but could see his 20-year term become 45.

The order notes that while it was too late for Pinkas to bring up some legal issues, a “claim that a sentence is void may be raised at any time.”

Pinkas was originally sentenced to 20 years, at the bottom of the statutory range of 20 to 60. Under Illinois law, the court was required to add 25 years for use of a firearm, but didn’t. That was the mistake Pinkas used for leverage to obtain a trial.

On March 21, Judge James Hackett allowed Pinkas to withdraw the plea. Jury selection began today.

Pinkas claimed he only meant to scare Sharon L. Reynolds, 37, with a shotgun when it discharged during an argument, killing her the night of Feb. 14, 2004.

Marlon A. Walker covers Illinois general news for STLtoday.com and the St. Louis Post-Dispatch.