09/05/2014 03:58 EDT | Updated 11/05/2014 05:59 EST

Mr. Big sting led to Harley Lawrence murder charge

The pair appeared in provincial court in Kentville on Thursday to set dates for a preliminary inquiry.

Lawyers for both men said they would agree to a trial on a charge of second-degree murder. But they want a preliminary inquiry for the Crown to prove that the higher charge of first-degree murder is warranted.

The decision the judge and lawyers referred to is the case of Nelson Hart of Gander, N.L.

Hart was the target of a so-called Mr. Big sting, where undercover police officers posed as criminals to persuade him to admit to past crimes.

Sources tell CBC News that Kyle Fredericks was the target of such an undercover operation in the months leading up to his first-degree murder charge. The technique was apparently not used against his co-accused, Daniel Surette.

Three murderers jailed after Mr. Big stings

The Mr. Big sting has been used in at least three high-profile murder cases in Nova Scotia. All three resulted in guilty pleas and convictions.

Almost a year later, Boudreau confessed to choking the girl and dumping her body.

Jason MacRae confessed to killing his wife, Paula Gallant, five years after the crime. 

Her body was found in the trunk of her car at the school she taught at on Dec. 27, 2005. In March 2011, MacRae pleaded guilty to murdering her over a $700 gambling debt. He was charged after he provided details of his crime to undercover police posing as gang members.

Weir-Hales pleaded guilty to second-degree murder and must serve a minimum of 15 years of a life sentence before she can apply for parole.