Derek James Kembel, 24, was last seen leaving a Dauphin bar on the evening of Feb. 28, 2003. His body has never been found. (North American Missing Persons Network)RCMP used an undercover "Mr. Big" sting to gather evidence in an eight-year-old missing person's case in Dauphin.

Christopher Robin Shewchuk, 29, was arrested last Sunday and charged with first-degree murder in connection with the disappearance of Derek James Kembel. Kembel, 25, was last seen leaving a Dauphin bar on the evening of Feb. 28, 2003. His body has never been found. Police have also charged Thomas Ronald Shewchuk, 60, with accessory after-the-fact to murder.

A so-called "Mr. Big" sting involves undercover police offering a job, money or prestige to a suspect who is induced to share a secret. It has been used in other cases in Manitoba and also, recently, in Nova Scotia.

But the Shewchuk's defence lawyer, Greg Brodsky, said the tactic is unreliable and many jurisdictions don't use it. He said cases have been overturned on appeal because confessions obtained in this way aren't considered reliable. "It's not universally used in the United States or Australia, United Kingdom," Brodsky said. "They've banned it because they're concerned ... that if a conviction is rendered it wouldn't be a safe foundation."