Horrific details in the case of accused murderous Massachusetts mom Lindsay Clancy, who fatally strangled her three young children, will begin pouring out in court this week. 

Clancy’s legal team and the prosecution are expected to deliver highly anticipated opening statements in the triple-slay trial starting Monday morning, after a jury pool of 12 women and six men were locked in last week. 

The killer mom’s ex-husband, Patrick Clancy – who now lives in New York City with his new wife, infertility specialist Rachel Danis – is slated to testify as the first witness. 

Patrick – who discovered his and Lindsay’s three kids dead in their Duxbury home in January 2023 – is going to take the stand for the prosecution first, though he’s also on the defense team’s witness list, according to the Boston Globe.

The dad will likely face questions about his marriage with Clancy, their home life and his perception of his then-wife’s mental state leading up to the grisly killings, as well as his version of events that fateful day, the outlet reported. 

Lindsay’s lawyer, Kevin Reddington, will then have the opportunity to cross-examine Patrick and bring up points that are essential to the defense’s insanity argument, including the mom’s repeated efforts to get help for postpartum psychosis. 

The trial’s outcome will hinge on whether jurors believe the former nurse was suffering from a psychiatric episode, worsened by a cocktail of antipsychotic medications, when she strangled the children to death, according to experts. 

“The whole case is just her state of mind and whether she was aware of right from wrong and literally if [she was aware] what she was doing was going to end up killing her kids,” former prosecutor Mark Bederow told The Post. 

Clancy is accused of using exercise bands to choke the life out of her children in the basement of the family’s home before becoming paralyzed from the waist down from a later botched bid to kill herself. 

Prosecutors are expected to argue that the mother wasn’t suffering a mental break. Rather, they will reportedly present Internet searches and other evidence showing she was lucid enough to methodically plan how to get her husband out of the house that day so she could be alone with their children: Cora, 5, Dawson, 3, and 8-month-old Callan.

Patrick filed a last-minute motion last week seeking to prevent the public from hearing a recording of his 911 call, as well as seeing any “pre-incident,” crime scene or autopsy photographs of the three kids, during the trial, according to court papers.

He also requested that the display of any clothing that once belonged to his children be restricted in the courtroom. 

Judge William Sullivan reportedly granted the motion Friday, ordering media not to record, display, reproduce, distribute or otherwise disseminate the 911 call and autopsy photos.

But the evidence will be shown to everyone present in the courtroom – and reporters are allowed to discuss its contents, WCVB reported.

The defense team filed an additional motion to try to prevent more than a dozen cops and firefighters who responded to the horrific murder scene from testifying. 

The first responders already “testified in the grand jury to basically the same facts” and “repeated testimony of this nature is and would be irreparably prejudicial,” Reddington wrote in the filing.

Regarding that motion, the judge said he will sidebar with both the defense and prosecution lawyers before each new witness takes the stand so he can decide whether their testimony is necessary, the outlet reported. 

The jury pool was locked in Thursday, after more than 300 potential jurors were questioned and excused from the case – including many who left the Plymouth County courthouse in tears from having to contemplate the harrowing killings. 

The wheelchair-bound 35-year-old Lindsay appeared to frown and gaze intensely at potential jurors as the arduous process dragged on.

Her parents, Paula and Mike Musgrove, sat stoically in the gallery behind her, courtroom photos show. 

Only 12 jurors will deliberate once all of the evidence has been presented in the trial, which is slated to last up to two months and feature testimonies of up to 200 witnesses. The other six selected panelists are alternates.

All prospective jurors were required to answer a lengthy list of personal questions last week, including whether they had been diagnosed with postpartum depression or an anxiety or bipolar disorder or whether any of their family members had, according to the Boston Globe.

They were also asked whether they or a family member had any experience with the mental-health system that would prevent them from being impartial and if they could remain open-minded about the defense’s insanity argument, the outlet reported.

In addition, they were required to disclose whether they have had any relationship to witnesses who are expected to testify, according to WCVB. 

After filling out the lengthy questionnaire, each prospective juror was sent into the Plymouth County courtroom to be interviewed by Reddington, Assistant District Attorneys Jennifer Sprague and Shanan Buckingham and Judge Sullivan. 

Although those conversations were private, the Boston Globe reported that several candidates were overheard admitting that they couldn’t fairly judge Clancy – and multiple potential jurors were promptly excused after bursting into tears during the questioning. 

A box of tissues was even placed inside the courtroom for individuals who grew emotional while grisly case details were discussed, according to the outlet.

The jury selection process faced even more setbacks when three jury members requested to be removed from the case earlier this week.

“I just don’t know if I can handle being on the jury,” said an emotional young man, who had previously been selected to serve on the jury, to Judge Sullivan on Wednesday.

Two more jurors were cut loose Thursday.

Should Lindsay be found not guilty by insanity, the former labor and delivery nurse at Mass General Hospital would reportedly remain committed to a state psychiatric hospital and only walk free in the future if doctors conclude she does not pose a danger to society.