The judge plans to announce his decision on Wednesday morning.
The defense wants the case thrown out saying this trial has been filled with illegal evidence.
Peterson is accused of killing his third wife Kathleen Savio but could be a free man on Wednesday.
This is the third time the judged has stopped prosecutors in their tracks and considered a mistrial and legal experts say will county prosecutors have only themselves to blame.
The testimony centered around a time Peterson is said to have gone into Savio's home wearing black swat gear, gloves and wielding a knife. He allegedly held that knife to his ex-wife's throat and threatened to kill her.
Earlier, out of the jury's presence, the judge warned prosecutors not to ask about a restraining order, but assistant state's attorney Kathleen Patton did anyway.
"Did she tell you she wanted to get an order of protection?" Patton asked the witness.
Defense lawyers jumped from their seats and demanded a mistrial.
"The reason the state is doing this is they have no confidence in their case," said Peterson defense attorney Joel Brodsky. "They don't believe they can win unless they can get in inadmissible, illegal evidence."
Prosecutor Patton immediately realized her mistake and buried her head in her hands.
The judge accused prosecutors of trying to introduce what he called "explosive" evidence he had already barred. And it's the third time it's happened.
"Have you ever seen a case file where the state purposely went against court orders?" the judge asked as prosecutors pleaded for mercy and no mistrial.
"We stand ready to appear in court (Wednesday) morning and receive the judge's decision and proceed with this trial," said Will County States Attorney James Glasgow.
"I'm really hopeful the judge will rule fairly," said Stacy Peterson family spokesperson Pam Bosco. "He's going to strike the statement and we're going to move on with this case."
Law professor Richard Kling doubts there will be a mistrial but says prosecutors' repeated mistakes are serious.
"They're doing awfully stupid things, they really are," Kling said. "If a defense lawyer did that I would suggest he would probably be spending the night in custody."
Patton asked the judge to punish her for the error, not the entire prosecution team.
Options for the judge include simply telling jurors to disregard the statement all the way up to declaring a mistrial, but if he believes prosecutors are intentionally making these mistakes hoping for a do-over.
That conduct would be so serious that Peterson could go free.