A prosecutor at Lindsay Clancy’s trial was caught on a mic saying, “Shut her up’’ as the killer mom wailed when autopsy photos were shown of her baby in court, the defendant’s fuming lawyer said Friday.

Clancy lawyer Kevin Reddington protested to the judge after a break that he needed to raise an issue in the Massachusetts horror case.

Judge William Sullivan said he wanted to take the issue to sidebar, even though the jury wasn’t back in the room yet.

“I don’t want to go to sidebar. I really don’t want to go to sidebar,” said Reddington — whose client, a 35-year-old former labor and delivery mom — fatally strangled her three young children with exercise bands.

“They got picked up on a hot mic saying ‘Shut her up,’ during the playing of the autopsy,” Reddington said of Thursday’s alleged incident.

It wasn’t clear who the “her’’ was that the lawyer was referring to.

But the prosecutor allegedly made the comment while medical examiner Dr Kimberly Springer was on the stand and the court was shown autopsy photos of Clancy’s 8-month-old baby Callan — a moment that the mom loudly sob and wail.

“I just want to find out what the issue is,’’ the judge said. “There are a lot of privileged issues.’’

Here’s the latest on Lindsay Clancy’s trial for allegedly murdering her three children:

Then the lawyers all went to sidebar.

Clancy’s lawyers claim she was in the throes of a psychotic postpartum episode when she killed her little kids.