Two convicted drug dealers took the stand today during Alicia Murphy's murder trial to try to discredit the evidence given Wednesday by an 11th-hour defence witness, who also dealt drugs in Whitehorse.

Murphy has pleaded not guilty to killing 28-year-old Evangeline Billy and dumping her body in the Yukon River, where it was found on June 22, 2008.

Crying and shaking with stress and fear, the witness – whose identity is protected by a publication ban – told the 12-person Yukon Supreme Court jury about seeing two men standing over a body on the banks of the Yukon River some time during the summer of 2008.

She said she had no idea when the incident occurred, only that it was sometime between April and September when she was living in Whitehorse.

"It could have been a different time,” she said when pressed for a specific date. "I was pretty messed up the whole time I was here.”

She said she was dealing and using drugs at the time and had gone to the river to look for her boss, Jimmy Campbell, to get some crack.

When she parked her car near the 98 Hotel, she told the court, it was late and no one was around. She walked toward the water and heard two male voices arguing, and recognized one of the voices as Campbell's.

She started walking toward the voices, she said, and saw Campbell and another man, "Big Mike” McQuaig, standing together not far from the edge of the water.

On the ground between them, she said she saw the body of a small woman with long hair.

"I didn't see much because Jim started dragging me up the bank,” she said. "... I seen somebody laying on the ground .... I didn't see her face or anything.”

She said Campbell hustled her back to the car and told her to go home.

The next day, she said, she drove to Carcross with Campbell and noticed he was acting strangely.

"He wasn't himself,” she said. "... He was angry all the time, he was pacing, cursing under his breath.”

At the time, she was too afraid to say anything to him, she said.

"He would have flipped out if I'd asked him any stupid questions.”

She also said Campbell and McQuaig had threatened her with violence if she ever spoke about them or their business.

"(They said) if I talked about anything to anybody that I could get hurt real bad,” she testified.

Several times throughout her testimony, the woman broke down and refused to go on.

She didn't want to name the dealer she worked for, nor any of the other people who sold drugs for him. She said she was afraid for her safety.

Justice Ron Veale, who is presiding over the trial, gently told her it was important that she tell the court what she knew.

Defence lawyer Gordon Coffin led the witness using information she gave to police earlier this year.

The woman spoke to homicide investigator Sgt. Mark London in May 2009, shortly after being released from jail in the Northwest Territories, the court heard.

During the first conversation she had with him, she allegedly contradicted herself several times, saying she saw something on the river, then saying she was never there, according to Crown prosecutor Noel Sinclair.

She also said she had seen Murphy at the scene, Sinclair alleged.

"I was intoxicated,” she said of that first conversation with London, adding she could not remember any of what she had said to the sergeant.

Murphy's trial was originally scheduled to begin on June 1 but was postponed so investigators could look into the woman's allegations, which were made in late May.

The woman was the last person to take the stand for the defence. McQuaig and Campbell were followed as rebuttal witnesses for the Crown.

According to Campbell, he never had any direct contact with the defence witness. He admitted to being an upper-level crack cocaine dealer in 2008, and said he did business McQuaig.

For his part, McQuaig admitted dealing drugs in Whitehorse, then recanted and said he only dealt in 1999 when he was convicted. But Campbell gave extensive details of the men's operation.

McQuaig supplied drugs to Campbell and others, who would then sell it to street-level dealers, Campbell said.

Among the street-level dealers were Campbell's daughter and the defence witness, who worked as a team, Campbell said.

He didn't deal directly with the woman, he testified, although she was constantly calling him and trying to get drugs from him.

"Never at any time did I give her any drugs,” he said about the woman, explaining that his daughter was the go-between.

During her testimony, the woman said: "Evan (Billy) owed Jim money for drugs,” but Campbell denied that statement.

"If Evan received any drugs from me, they didn't come from my hands,” he said, adding no one who bought drugs on the street would ever owe him money because he only sold to other dealers.

Campbell, who was arrested on drug charges last December and has been under house arrest since his release in June, said he didn't even meet the defence witness until July of 2008, when she started working with his daughter.

He said he couldn't remember where he was the weekend Billy was killed, but he knew McQuaig was in Edmonton because Campbell had sent his son down to stay with him.

McQuaig gave the same alibi, saying he drove down to Alberta on Wednesday, June 18, and picked Campbell's son up at the airport on June 20.

The boy stayed with McQuaig in Edmonton until after Canada Day, McQuaig said.

Campbell said he wasn't sure how long his son and McQuaig were out of the territory, but knew it was at least two or three weeks.

Campbell said he was using heavily the whole time McQuaig was gone.

"Usually when Mike left town, that was my time to really hit the drugs,” he said.

McQuaig doesn't smoke crack, the two men said, with Campbell adding: "Mike doesn't like to see people using drugs – going in debt, you know – because if I was using drugs, it was his drugs I was smoking.”

Both men denied having anything to do with Billy's death.

The trial is slated to run for another week, although both sides have said they are ahead of schedule.

The Whitehorse court room has been packed with friends and family of both the deceased woman – who is originally from Carmacks – and the accused, whose family is based in Carcross.