A Medicine Hat woman convicted of murder on the testimony of a witness with inconsistent testimony and an IQ of 50 has been ordered to stand trial again by the Alberta Court of Appeal.

In January, Connie Oakes asked the Alberta Court of Appeal to overturn her conviction and either order a new trial or an outright acquittal.

In a split decision released on Wednesday, the panel of judges acknowledged the issues at her first trial.

"Any undue weight the jury may have placed on Ms. Scott's testimony is of concern because her testimony was particularly unreliable and could otherwise have left the jury with a reasonable doubt," reads the decision.

"We conclude that a miscarriage of justice has occurred with the result that the appeal is allowed and a new trial is ordered."

Casey Armstrong, 48, was found dead in his Medicine Hat trailer in May 2011. He had been stabbed in the neck.

Connie Oakes's aunt, Linda Oakes, right, and eight other members of her family travelled from Sask. to listen to arguments in her appeal earlier in the year. (Meghan Grant/CBC)

Two women, Oakes and Wendy Scott, were charged with murder. Scott pleaded guilty to second-degree murder but in October, the Alberta Court of Appeal overturned her conviction and ordered a new trial.

The Crown consented to a new trial on the basis that the evidence presented to the original trial judge did not support a finding of second-degree murder.

There were about 50 contradictions in Scott's testimony and she has an IQ of about 50.

There was no forensic evidence presented at Oakes's trial linking her to the murder; rather the prosecutor relied on Scott's testimony.

Despite the inconsistencies in Scott's evidence, a jury found Oakes guilty of second-degree murder and she was sentenced to life in prison with no chance of parole for at least 14 years.

In an prison interview with the CBC's Fifth Estate recorded before the decision was handed down, Oakes maintained her innocence and said several people were responsible for her conviction.

"I blame Wendy for putting it out there," Oakes said. "I blame the investigators, Medicine Hat City Police, part of them, and the prosecutor."

'No jury should've convicted her'

Oakes's Edmonton trial lawyer Daryl Royer said the outcome of the trial had him doubting the legal system and considered quitting law.

"If the law goes this far astray or this strange, then it causes me to doubt my faith in it," Royer said. "On the evidence that the jury had, there was no chance of conviction."

"No jury should've convicted her, and she maintains that she didn't do it, and Wendy Scott is saying, 'Actually, I wasn't there, and neither was Connie Oakes.' "

