The suspect in the Lyle and Marie McCann murder case may be getting a break on eight unrelated criminal charges.

Travis Vader appears in Edson Provincial Court in May. (CBC)

Travis Vader was supposed to be sentenced Friday on eight charges including the theft of a truck, trafficking methamphetamine and poessession of an illegal revolver.

The charges date back to June 2010, one month before the McCanns went missing.

Vader was convicted in May due in large part to testimony from a pair of key witnesses, two female accomplices in a Barrhead, Alta, crime spree.

But in court Friday, Vader's lawyer told the judge she did not know about some of the of statements made by the witnesses to police.

The court system has strict rules demanding the Crown disclose all evidence to the defence.

In court, prosecutor Michelle Doyle told Justice June Ross she did not know the statements existed before Friday, but admitted they're relevant.

"I did not know of their existence until now," she told the court. "I would have disclosed them if I'd known about them, because I consider them to be relevant."

Vader's lawyer Anna Konye said she will apply for a mistrial or a stay of proceedings.

The application will be made Oct. 19th.

Vader remains in custody facing first degree murder charges in the July 2010 deaths of Lyle and Marie McCann.

The bodies of Lyle, 78, and Marie, 77, have never been found.

With reports by CBC's Janice Johnston