Luka Magnotta trial: Bloodstains described by forensic expert

A forensic biologist guided the jury in the Luka Magnotta first-degree murder trial methodically through each bloodstain found at the crime scene, and revealed she was given clues about where to search for blood when she watched an online video showing parts of the crime.

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Jacinthe Prvost, a forensic biologist with 18 years ofexperience, was called to the apartment in Montreal's Snowdon neighbourhood in the early hours of May 30, 2012.

She testified investigators informed her a video had been posted online, and she decided to watch it twice - once in the command post the police had set up to give her an idea of where to concentrate her search, and a second time while examining the exhibits she took from the scene.

The witness spent more than two hours analyzing bloodstains and spatter at the scene, and later treated 94 pieces of evidence as she compiled her report.

Prvost told the court she examined stains found in the roomsandthrough DNAtestingidentified the blood as belonging to the victim, 33-year old Jun Lin.She also found the DNA of a man later identified as the accused, Luka Magnotta.

Magnotta has pleaded not-guilty to first-degree murder and four other charges, buthas admitted to the physical act of killing Lin, along with the facts outlined in the other charges. His lawyer intends to prove Magnotta is not criminally responsible because of mental illness.

The Crown alleges the killing was premeditated.

Blood stains found in each room

The forensic biologist described in detail the numerous little blood spots found near the window and radiator close to the bed. She explained to the jury that small drops indicate a forceful blow was used, and because of the size and angle of the drops, the witness presumedthe blow occurred near the foot of the bed.

Prvost noted the bedsheets had folds that indicated they were newlybought, and there was a burgundy shower curtain on the bed underneath a brown flat sheet.

There was an enormous amount of decayed blood on the bed, the witness testified, and blood seeped straight through the mattress, which Prvost saidlooked as if it had been flipped in a possible attempt to hide the large stain.

The witness also detailed the large bloodstains found in the freezer and the refrigerator, saying it looked as though something was placed on the grillerack that was dripping with blood, forming a pool at the bottom.

Prvost said blood in the bathroomsink and bathtub was diluted, and the sink was likely wiped clean. The witness explained she noted all the stains found, but did not analyze all of them, since she believed she had enough to determine whom the blood belonged to.

Prvost also walked the court through the exhibits she examined, including several items of clothing that she testified had traces of DNA belonging to both the victim and the accused.

Officer recalls strong smell from crime scene

Earlier in the day, the trial briefly heard from the first patrol officer to enter the apartment on May 29, 2012.

Peter DAvola, who was given the task of going in to find either possible victims or a suspect, testified he was struck by a strong chemical smell, stronger than bleach, mixed with the smell of a body, when he quickly walked through the apartment.

He stayed a total of 15 minutes, he told the court, and found all the windows and doors shut butbalcony door unlocked.

The officer, dressed in uniform, testified that he glanced around the studio apartment and noticed a lime juice bottle on a table andwhat looked like bloodstains.D'Avola said he was most struck by the sheets found on the bed.

He said they looked too big, as if they were king-sized, for what seemed to be a double bed.

Prvost will be cross-examined by the defence on Wednesday morning.