Lindsay Clancy holdout juror says he had no doubt she deliberately killed her children

The lone holdout juror in the trial of Lindsay Clancy has said he "didn't have any doubts" that she was criminally responsible for killing her three children.

"Based on all the physical evidence, key witnesses and what the prosecution presents, I thought it was enough proof that she knew exactly what she was doing and planned it," Michael Desronvil said in a statement to CBS News, the BBC's US partner.

The judge declared a mistrial on 4 September after the jury failed to reach a unanimous verdict following nearly 40 hours of deliberating.

Clancy admitted to the killings but her lawyers argued she had been suffering from postpartum psychosis. Prosecutors said the killings were calculated.

The 36-year-old was charged with three counts of first-degree murder after strangling Cora, five, Dawson, three, and Callan, eight months, at the family's Massachusetts home before jumping out of the second-floor window.

To find Clancy guilty, jurors had to be unanimously convinced beyond reasonable doubt that she intentionally killed her children and that she did not do so as a result of postpartum psychosis, a rare and serious condition.

The jury - nine women and three men - considered a range of options including not guilty by reason of insanity, manslaughter and first-degree murder.

Several jurors have said following the mistrial being declared that the panel was ultimately divided 11-1 in favour of finding Clancy not criminally responsible.