Lindsay Clancy’s lawyer officially filed a Hail Mary bid Thursday asking a judge to find the killer mom not guilty by reason of insanity despite her high-profile case ending with a hung jury.

Defense lawyer Kevin Reddington argued in new court papers that prosecutors at her widely watched five-week trial failed to prove that the 36-year-old Duxbury, Massachusetts, mother knew what she was doing was wrong and could follow the law when she strangled her three kids on Jan. 24, 2023.

“No rational jury could find beyond a reasonable doubt that she had no mental disease or defect when the Commonwealth’s own proof established that she did,” Reddington, 75, wrote in the papers.

The veteran defense attorney says he plans to argue his motion further at Clancy’s next hearing on Sept. 29 when a potential new trial date could be set for her.

Boston lawyer Peter Elikann told The Post Monday that the likelihood of the type of motion Reddington filed succeeding is “rare to the extreme.”

Reddington asked the jury to find Clancy – a former labor and delivery nurse – not criminally responsible, claiming she was suffering from severe postpartum psychosis and hallucinated a voice forcing her to kill Cora, 5, Dawson, 3, and Callan, 8 months, before she attempted suicide.

However, prosecutors alleged she was lucid enough to carefully plan and execute the horrific crimes.

The prosecutors’ case attempting to prove “criminal responsibility was legally insufficient,” especially considering all of their forensic experts admitted Clancy “suffered from a serious mental illness” the day of the murders, the papers from Thursday claimed.

While experts for the prosecution and the defense didn’t all agree on what illness Clancy had at the time, they all admitted she was very sick, the papers said.

Prosecutors tried to use the fact that Clancy drove her car that day, made phone calls and sent her husband on errands as proof she was in her right mind, but Reddington said a defense expert testified those basic functions could still be carried out by someone suffering from a psychotic break.

“Taken at their strongest, these show that Ms. Clancy could perform familiar tasks and act in sequence. They do not show that she could appreciate wrongfulness or conform her conduct to the law,” Reddington claimed.

The attorney also implied jurors’ statements in the media over the past few days could be considered an “unannounced verdict,” which would block the case from going to trial a second time under double jeopardy laws.

Ultimately, Reddington asked the judge to deem the evidence against Clancy insufficient and find her not guilty by reason of insanity.

The defense attorney has made this motion two other times throughout trial, which were both denied by Plymouth Judge William Sullivan.

The judge declared a mistrial Friday after the jury sent out its third impasse note saying they were deadlocked.

The day before, jury foreperson, Roni Carlson, notified Sullivan that a single male holdout juror was allegedly refusing to follow the court instructions on reasonable doubt, blocking the panel from finding Clancy not criminally responsible.

Sullivan then questioned each juror one by one and re-read the group of nine women and three men his instructions on the law on reasonable doubt. The following day, the panel announced for the third time they were deadlocked, and Sullivan ultimately declared mistrial.

Sources: NY Post