CHICAGO (CBS) — A man convicted in the 1983 murder of a Rogers Park couple could get a step closer to a new trial, depending on how the Illinois Torture Inquiry and Relief Commission votes on Wednesday, and on Tuesday the victims’ relatives were preparing their remarks.

Jerry Mahaffey was convicted decades ago of killing Dean and JoEllen Pueschel, and beating their 12-year-old son almost to death.

It was detectives under notorious Chicago Police Cmdr. Jon Burge who worked the case, which brought Mahaffey’s conviction into question.

The state’s Torture Inquiry and Relief Commission voted two years ago to send the case to a judge to decide whether Mahaffey should get a new trial, but the Pueschels’ family learned it had been excluded from the commission hearings, so the process began again.

On the eve of another commission vote, JoEllen Pueschel’s brother was apprehensive.

“They voted once to send this over, and they messed up. So there would be egg on their face if this case does not get referred, and I think there’s a lot of internal politics at play on this commission, and they don’t want egg on their face,” Joe Heinrich said.

Heinrich said his family is allowed 15 minutes to try to convince the commission that Mahaffey was not tortured and does not deserve a new trial.

He said 15 minutes is not enough to tell their side.

“We are normally a peaceful and quiet family that doesn’t go looking for a fight,” Heinrich told WBBM in an email. “But we are angry and frustrated beyond comprehension and our anger has become quite evident. We detest having to be this way but we didn’t create this situation. We dream of the day when sleepless nights are a thing of the past.”

In a written statement, a spokesman for the commission says that “confidentiality requirements of the statute prevent commission staff from commenting about an active investigation.”