Mark Lange shared his cell at the Whitehorse RCMP detachment with an undercover officer, Yukon Supreme Court heard Thursday afternoon during the second-degree murder trial of Lange and Dean Boucher.

Carcross hotelier Robert Olson's body was found in the Wolf Creek subdivision on Dec. 27, 2004.

RCMP Cpl. Donald Aubon testified under cross-examination by Lange's lawyer, Andre Roothman, that the placement of an undercover officer in a cell has been used regularly in the past if there is one available.

When he was stationed in Alberta, Aubon said, an undercover officer was put in the cell with the accused almost everytime there was an armed robbery, for example.

Justice Leigh Gower would not allow evidence on what was said by Lange to the officer.

Boucher's lawyer, Keith Pakkari, objected to the questions, arguing it would be hearsay evidence.

Aubon did have knowledge of what Lange had said, noting he got it from the officer who was in the cell.

Before his cross-examination, under questioning by the Crown, Aubon reviewed the scenario of events leading to Lange's and Boucher's arrests.

Aubon was involved as the lead investigator.

At around 2 p.m. on Dec. 27, 2004, he said he was contact by Sgt. Frank Campbell about a suspicious death.

After getting a brief summary, he went into the detachment for a debriefing with others on the major crimes unit.

There, he learned that at 12:38 p.m., an anonymous phone call came in from a female.

She said the individual involved in the suspicious death was Lange, who was probably at the bus depot and could be travelling under a different name.

Only seven minutes later, at 12:45 p.m., Dean Johns, who Boucher is also known as, went into the detachment saying he knew who was responsible for Olson's death.

'It certainly got our attention,' Aubon said of the two reports coming within seven minutes of each other.

Aubon said he was told Olson had been reported by the Carcross detachment as missing three days earlier.

Olson's truck was also found prior to the anonymous call.

Officers were sent to the bus station to see if they could find Lange. However, they weren't able to locate him, and since the bus had already left the station, the Watson Lake RCMP detachment was contacted to make sure Lange wasn't on the bus.

Lange wasn't found until he turned himself into police three days later.

In the meantime, police also worked on trying to find out who the anonymous caller was. Though the call was traced to a pay phone at the Wal-Mart store, they were unable to identify the caller.

Interviews were also done with Boucher and the body was located in Wolf Creek. Although other officers were involved in taking evidence from inside the Caribou Hotel for the case, Aubon never went inside.

On Dec. 28, based on the information available to that point, Boucher was charged with accessory after the fact.

A warrant was issued for Lange's arrest on Dec. 29 but he wasn't located until Dec. 30.

Aubon said he was in the middle of a briefing on the case that day when front desk staff came in to tell the officers Lange had come into the front desk.

Lange, who was arrested for second-degree murder, was interviewed. After agreeing to a re-enactment, he later went back to the Caribou Hotel in Carcross to tell his version of events at the scene.

Police continued to investigate from there as well.

As recently as May 10, Aubon travelled from the Caribou Hotel to Whitehorse measuring the distance and time taken, including the walking distance from Wolf Creek to McCrae.

Both Lange and Boucher told RCMP after a fight at the Caribou Hotel (each have told different versions of the fight in seperate police interviews), Olson was placed in his truck and they drove to Whitehorse.

In Wolf Creek, they stopped and the body was dumped. When they drove off, the truck got stuck and they ended up walking to McCrae.

While Aubon was the Crown's final witness in the case, Roothman has yet to cross-examine Const. Bradley Wirachowsky.

A legal question came up Thursday before the cross-examination was to begin.

Gower was scheduled to rule on that question when court reconvened this afternoon.