SAINT JOHN, N.B. -- The person who killed Richard Oland would have had a significant amount of blood on their hands and clothes, a blood spatter expert testified Thursday as defence lawyers for Dennis Oland began making their case in the lengthy murder trial.

Dennis Oland has pleaded not guilty to a charge of second-degree murder in the July 6, 2011 death of his father, a well-known New Brunswick businessman, whose family operates Moosehead Breweries.

Oland's badly beaten body was found in a pool of blood on the floor of his Saint John office the next day.

He had suffered 40 blunt and sharp force blows to his head and neck, and another six sharp force blows to his hands.

Patrick Laturnus, a retired forensic specialist for the RCMP and now a consultant, said he examined all the forensic evidence from the case including the hundreds of blood spatter stains that radiated 360 degrees around the victim's body.

Laturnus said he would expect there would be significant spatter on the assailant.

"There would have been so much blood on the jacket you would have been able to see it in a photograph," he said.

The trial heard during the Crown's case that there were three confirmed blood stains on Dennis Oland's jacket that were very small in size and hard to detect because of the colour of the material.

Laturnus said there's no way to determine how that blood got on the jacket or how old it was.

Under cross-examination, Crown prosecutor P.J. Veniot asked Laturnus if he could be wrong about the amount of blood on the assailant.

"No," Laturnus replied.

"Are you saying the assailant would have enough blood on them that they would be concerned about visible staining?," Veniot asked.

"Yes I am," Laturnus answered.

Laturnus said based on patterns in the blood spatter, the attack on Oland started while the victim was seated in his chair and ended when he was on the floor.

The defence plans to call another forensic witness on Monday.

Dennis Oland's lawyer said his client will also testify during the murder trial.

Gary Miller presented his opening statement to the jury in New Brunswick's Court of Queen's Bench, arguing that the Crown had not proven its case.

"Let me make one thing perfectly clear: to be sure it is our position that the Crown has not presented a case that satisfies the legal burden on this charge," Miller said.

Miller said the trial, into its 11th week, is not an ordinary murder trial, and the second longest in his career.

He said Dennis Oland and his family have lived under intense media scrutiny for four years.

"It will soon be time for him and some of his family members to speak publicly for the first time about what they know about any circumstances in this long ordeal," he said.

In addition to Dennis Oland, the defence will call Oland's wife Lisa, his sister Jacqueline Walsh, his uncle Jack Connell and his mother, Connie Oland.

"At the end of the day you will see the only verdict you can come back with is not guilty," Miller told the jurors.

The Crown wrapped up its case Wednesday with a DNA expert who testified that samples taken from a sport jacket seized by police from Dennis Oland's home matched the profile of his father.

The Crown presented witnesses that said Dennis Oland visited his father at his office on the evening of July 6, 2011 and was the last known person to see him alive.

Saint John Police considered Oland a suspect when they interviewed him on the evening of July 7. He told police he had been wearing a navy blazer when he visited his father, but witnesses and security camera video shown during the trial show him wearing a brown sports coat.