The Supreme Court of Canada will hear a Crown appeal against a Nova Scotia woman who was acquitted of trying to have her husband killed.

Nicole Ryan said she tried to hire a hit man to kill her spouse in 2008 because she was desperate after years of his abuse and death threats against her and her daughter.

The hit man turned out to be an undercover Mountie.

Ryan's lawyer successfully argued that she was acting under duress because she was the victim of prolonged abuse by her husband and that he had threatened to kill her and their child.

She said she believed he would carry though on those threats and that the police wouldn't be able to stop him.

The trial judge accepted her defence of abuse and acquitted her. The Nova Scotia Court of Appeal also dismissed the Crown's appeal of the case.

Crown attorney William Delaney argued during the appeal that the duress defence only applies when someone is forced by threats to commit a crime against a third person.

Delaney said he was pleased that the Supreme Court will hear the case, saying he will argue again that duress didn't enter into this situation.

"Our main point is simply that duress didn't apply," he said in Halifax. "This case for the first time applied duress where there are only two people involved."

He explained that a classic case of duress would involve someone being forced into committing a crime against someone by a third party under threat of force. For example, Delaney said it could involve a robber holding a gun to someone's back and ordering them to demand cash from a teller under the threat of harm.

The Crown also argued that even if the argument did apply, Ryan's claim that she was under duress didn't have an air of reality.

The pair were not living together at the time the charges were laid and had been apart for several months.

Her husband lived in Kentville, while she lived in Digby County.

The court disagreed on both grounds for the Crown's appeal, saying the defence of duress could be applied to Ryan's case.

Ryan's defence lawyer could not be reached for comment.

Delaney said he hopes the appeal will clarify the definition of duress, which has two different versions in the Criminal Code and in the common law.

"We're hoping that that might be clarified on this sort of appeal," he said.

Delaney didn't want to discuss all of the possible outcomes of the case, but said the court could dismiss the appeal or find that there was no defence of duress and order a conviction.

As usual, the Supreme Court of Canada gave no reasons for its decision to hear the case.