Alicia Murphy admitted to beating Evangeline Billy on the night she died and manipulating her body to make it look like rape, the accused woman's sister told a jury this morning during the third day of testimony in Alicia's trial on a charge of second-degree murder.

"What were your sister's exact words to you, to the best of your recollection?” Crown prosecutor Noel Sinclair asked in Yukon Supreme Court.

"That she beat her up – went too far – that something went wrong and they propped her up to make it look like something else,” Tanya Murphy replied. Her voice was almost inaudible, and tears streamed down the 30-year-old woman's face.

Tanya told the court she had been hanging out with her sister on June 21, 2008; the night before Billy's body was found face-down and half-naked floating in the Yukon River at the foot of Wood Street in downtown Whitehorse.

The sisters, along with half a dozen friends, had been drinking at the Stratford Motel earlier that evening.

They went to Tanya's house after someone made a noise complaint, and kept drinking. Sometime before the off-sales closed, a few people including Murphy left to get more alcohol, Tanya said.

One of the women returned with a couple 15-packs of Budweiser and a bottle of vodka. Murphy came back a couple hours later, at about 2:30 a.m.

"She was a little irate, I guess,” Tanya said when asked about her sister's emotional state at the time. "She wasn't happy.”

Murphy wanted to take one of the cases of beer, Tanya recalled, and the two argued. Murphy left at about 3 a.m. with one of the 15-packs.

The next day, sometime in the late morning or early afternoon, Tanya said, her sister called to say Billy's body had been found in the river and she wanted to come over. When Alicia, arrived the sisters went up to Tanya's room.

"(Alicia was) shaky ... a little lost, a little dazed, spaced,” Tanya said. Alicia said "that she'd been beaten and violated,” Tanya recalled.

"She told me that she might have done something wrong ... that she was trying to roll (Billy) for money and stuff ... and they got in a fight.”

Tanya testified her sister then said she had propped the body up to make it look as if Billy had been raped.

"She wouldn't look me in the eyes,” Tanya said.

According to Tanya's evidence, Alicia said other people had helped her prop up the body but "she just said ‘they' she didn't say any names.”

"How did you feel about hearing this kind of information from your sister?” Sinclair asked.

"I asked her to leave.”

While Alicia was in the house, a couple of RCMP officers stopped by, Tanya said, and Alicia hid. She could not remember who they were looking for or what questions they asked.

Once Alicia was gone, Tanya said she told her partner what she'd heard and went looking for Warren Edzerza and Jack Ollie, two of the men who had been drinking at her house the night before.

She found them at the '98 Hotel, but neither one would talk to her, she said.

Before hearing from Tanya, the jury heard more about the cause of Billy's death.

Jurors looked through a collection of grisly autopsy photos yesterday afternoon and this morning as pathologist Dr. Charles Lee described the

injuries found on Billy's body as well as his conclusions on what caused them.

There were three major routes the doctor followed to determine the cause of death, he told the jury.

First, and most obvious, were the blunt-force injuries to Billy's head and body.

A thick gash started on the left side of her head disappeared behind her hairline. Shaving off the hair revealed three skull-deep wounds which left the doctor with more questions than answers.

The wounds were definitely not the result of blows with a long, straight object, he said, because they follow the curve of the skull. They could have been caused by "glancing blows” from a rock or the head being dragged or hit against something, he said.

"I even entertained the possibility of an animal attack,” Lee added.

He ultimately dismissed that idea because the wounds were not perfectly parallel as claw marks would be, nor was there any evidence of bite marks or claw marks anywhere else on the body.

The photos show a significant amount of bruising on Billy's body, but again the doctor could make no firm conclusions as to their cause.

Many of the bruises were consistent with "accidental trauma” – such as falling or bumping into things – but could also be the result of a struggle.

Some of the bruises were a few days old, while others had been sustained hours before Billy died.

"There were some that were a bit more suspicious,” he said, including possible finger marks on the inside of Billy's arm and a bruise on the back of her knee. It is unlikely those were caused by a stumble, Lee said. A bruise on her wrist could have been caused by her body being dragged.

There were some bruises on the woman's neck but no internal damage to support a theory of strangulation, he said.

Though gruesome, the injuries jurors saw on Billy's body were not what killed her. The doctor found Billy's lungs and sinuses were filled with water, meaning she was still breathing when she went into the river. The doctor concluded she died of drowning.

The wounds to her head were contributing factors, he said, as was the high amount of alcohol in her blood.

Lee classified the 338 milligrams per cent blood-alcohol level as "acute alcohol intoxication.” For comparison, he said the legal driving limit is 80 mg per cent.

"Three hundred and fifty is when I start to worry about actual death from intoxication,” he said.

Both the head wounds and the level of intoxication could have prevented Billy from protecting herself from an attack or getting herself out of the water, the doctor said, reiterating the fact he could not say if the head wounds happened before or after she went into the river.

The trial is being presided over by Justice Ron Veale, and will be decided by the 12-person jury.

The trial is scheduled to run for another two weeks.