In a 5-2 split decision, the court ruled in favour of April Halkett, who was found not guilty in June 2009 of abandoning the baby boy two years earlier in the store in Prince Albert, Sask.
Halkett testified at trial that she didn't know she was pregnant and left the store because she thought the child was dead. A store manager later pulled the baby from the toilet and he survived.
"We're done. It's over and that is a relief for my client," lawyer Pam Cuelenaere said after the decision was released Friday.
She said she phoned Halkett to give her the good news. The 26-year-old woman paused and took a deep breath.
"I think it's going to take her a bit of time to process this, because it has been ongoing for such a long period of time. But there's a lot of joy in moving forward."
The Crown appealed the case to the Saskatchewan Court of Appeal and then the Supreme Court and both upheld the findings of the trial judge.
He had ruled that he believed Halkett's testimony. She said she didn't know she was expecting a baby because she tested negative three times on home pregnancy tests and she was still getting her period.
She told the court she thought the child was dead because of its blue pallor and because it wasn't moving.
Lawyers for the Saskatchewan government had argued before the province's highest court that the mother had a duty to take reasonable steps to determine if her baby was alive.
But the Supreme Court concluded the trial judge was right to acquit Halkett.
"The trial judge found that the respondent honestly believed that her child was dead at birth and that this belief was objectively reasonable," Justice Thomas Cromwell wrote for the majority.
"As such, she was entitled to be acquitted based on the defence of honest and reasonable mistake of fact."
Halkett has said it came as a shock in the bathroom stall when blood started running down her leg and a baby dropped into the toilet. A woman in the next stall heard grunts and saw a pool of blood on the floor. She knocked on the wall and asked Halkett if she was OK. Halkett replied that she was.
She tried to clean up the mess with toilet paper and left the store without talking to anyone.
Moments later, two women in the washroom saw a tiny, purple hand poking out of the bloody bathroom tissue that filled the toilet. The store manager pulled the baby out and paramedics helped him start breathing.
Police released surveillance-camera photos of the mystery mother. Halkett came forward soon after upon learning the baby had survived.
The boy, who turns six next week, lives with another family, said Cuelenaere. But Halkett sees him on a daily basis.
"They have regular contact and that contact is very positive. They're going to be continuing to move forward from this."
Halkett's stepfather, Ken Charlette, told a local radio station, Missinipi Broadcasting Corporation, that she would one day like to regain custody of the child. He said the boy is happy and doing well.
"This affected the whole family," Charlette said. "When we got together this morning and sat with her — people were choking back tears because it’s all over now.
"Now it’s basically just time to get on with life."
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