The Supreme Court of Canada has decided not to consider an appeal from Newfoundland and Labrador's attorney general to review the Anne Norris case.

In 2018, a 12-person jury found Norris not criminally responsible in the death of Marcel Reardon, whom she admitted to killing by striking him repeatedly in the head with a hammer.

The Crown had filed an application to the Court of Appeal of Newfoundland and Labrador earlier this year to request a new trial, but that appeal was rejected in a unanimous decision.

The attorney general then filed an appeal to the country's top court.

But the Supreme Court of Canada has dismissed the appeal application. The court does not release its reasoning for decisions on whether or not to hear an appeal.

On the first day of the four-week trial in St. John's in 2018, Norris admitted to bludgeoning Reardon, 46, repeatedly in the head with a hammer, as well as placing his body under the steps of her St. John's apartment building, and then later disposing of the hammer by putting it in a backpack and throwing the bag into the harbour.

The backpack with bloodied clothes and the hammer were found days later.

Norris admitted to killing Reardon, 46, by hitting him repeatedly in the head with a hammer. (Submitted)

Norris's defence argued she was not criminally responsible, and much of her four-week trial was spent outlining her history of mental illness.

The Crown's argument was that she knew what she had done was wrong, and understood the consequences of her actions.

Jurors returned a unanimous decision of not criminally responsible after days of deliberation. Norris, 32, was placed in psychiatric care, to be released at the discretion of the review board.

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