Jurors in the trial of Lindsay Clancy are deadlocked after four days of deliberations, but a judge has asked them to keep trying.

Clancy, a resident of Massachusetts, is facing murder charges for killing her three children at their family home in 2023.

Her lawyer does not dispute that the 36-year-old former nurse killed the children, but argues that she was suffering from postpartum psychosis at the time and was unable to distinguish right from wrong.

After discussing the case for several more hours on Tuesday, jurors were sent home for the day and asked to return in the morning.

“I just want to thank you for all your hard work and commitment so far in this case,” the judge told jurors before sending them home.

The Massachusetts mother is charged with three counts of first-degree murder, as the prosecution argues she made a calculated, intentional decision to kill them.

The jury, made up of nine women and three men, began deliberating last week after hearing weeks of testimony from dozens of witnesses.

On Tuesday, audible gasps could be heard in the courtroom as Judge William Sullivan read out a note from the jury indicating that it was deadlocked.

Clancy, who was left paralysed after jumping from a second-floor window shortly after the killings, appeared stoic as she sat in a wheelchair beside her lawyer.

It is not uncommon for jurors in high-profile trials to struggle to reach a decision, and judges have protocols for such situations.

A deadlock among the jury such as this one happens in “complex and emotionally charged trials”, Heather Cucolo, a New York Law School professor and expert in mental health law, told the BBC.

“If the deadlock persists, the judge might issue an additional ‘dynamite’ instruction [known as a Tuey-Rodriguez charge in Massachusetts] to encourage the group to consider alternative perspectives and strive for an agreement while upholding their genuine convictions,” Cucolo said.

But it is “typically a last-ditch effort” from a judge, she said.

Criminal defence lawyer Elyse Hershon told the BBC she was not surprised to hear that the jury was deadlocked, as people had strong opinions on the case.

“The facts are difficult and a lot of the evidence is graphic so they have a lot weighing on them,” she said.

The judge can declare a mistrial if the jury is not able to agree on a verdict.

Clancy is accused of strangling her kids – Cora, five, Dawson, three, and Callan, who was eight months – with fitness bands in their Massachusetts home in January 2023.

The defence argues that Clancy was experiencing postpartum psychosis, a severe mental health condition that can develop after childbirth, and that she should therefore not be held criminally responsible for the killings.

If found guilty of first-degree murder, the intentional and premeditated killing of another person, Clancy will face a mandatory life sentence in prison without the possibility of parole.

She could also be found guilty of a lesser charge, including second-degree murder – committed with malice or extreme recklessness, but without prior planning – or manslaughter – unintentionally killing “by wanton and reckless conduct”. In either of those instances, she would face time behind bars.

If she is found not guilty by reason of insanity, she will not be set free – she would instead be sent to a psychiatric hospital where her status would be periodically reviewed. She could stay in hospital for the rest of her life.