EDMONTON - The man who gave a gun and a ride to James Roszko hours before he murdered four Mounties stood in court Tuesday, cried, and told the victims' families that he never foresaw the slaughter.

"I would like to apologize for my involvement in this tragic event," Shawn Hennessey said in a brief statement after sentencing arguments in Court of Queen's Bench.

"I'm truly sorry for the loss these families have suffered. In no way did I mean for any harm to come to anyone."

Hennessey, who had sat stoically in the prisoner's dock throughout the two-day hearing, wiped away tears while others in the gallery of the crowded courtroom struggled with their emotions.

The 29-year-old and his brother-in-law, Dennis Cheeseman, 25, are to be sentenced Jan. 30 in a case that evoked grief across the country and sparked debate about how RCMP handle potentially dangerous situations in rural areas.

On Monday, Hennessey and Cheeseman pleaded guilty to manslaughter in the March 3, 2005, deaths of RCMP constables Brock Myrol, Peter Schiemann, Anthony Gordon and Leo Johnston.

Roszko, using a semi-automatic .308 Heckler and Koch assault rifle, murdered them as they gathered evidence inside the Quonset hut on his farm near Mayerthorpe, northwest of Edmonton.

Cheeseman, when asked by Justice Eric Macklin if he wanted to make a public statement, stood and told court, "My lawyer's said everything for me."

The pair had been charged with first-degree murder, but pleaded out to the lesser charge. Both Crown and defence have submitted an agreed statement of facts on what happened, but are asking Macklin to impose radically different jail sentences.

Crown prosecutor David Labrenz is seeking a 10 to 15-year prison term for both, labelling their failure to stop Roszko or at least alert police to the danger "reprehensible, cowardly and extremely selfish."

But Hennessey's lawyer, D'Arcy DePoe, told court Tuesday his client should get about three years.

Hennessey, he said, had been in the thrall of a raving Roszko, who showed up at Hennessey's house that fateful night, brandished a gun and used the implicit threat of violence to coerce the two men into helping him.

"(Hennessey) was obviously frightened and intimidated," said DePoe. "He didn't feel there was an option."

Court has heard that Hennessey, a tire store manager from the nearby town of Barrhead, was partners in crime with the 46-year-old Roszko in the 280-plant marijuana grow operation Roszko was running inside his Quonset hut.

Roszko, noted DePoe, was feared around town for bullying and intimidation. He had criminal convictions for possessing stolen property and for sex assault. He threatened and intimidated police. There were allegations he sexually abused young boys at gunpoint. He uttered threats and damaged property. The Crown considered locking him up indefinitely as a dangerous offender. He was a ticking time bomb wrapped in a cocoon of misanthropy and self-hate.

"Mr. Hennessey had never had a disagreement before (with Roszko), but anyone who knew him knew you didn't cross this man," said DePoe.

But on the night of March 2, 2005, Roszko showed up at the home unannounced and demanded Hennessey either cross him or join him, said DePoe.

Earlier that day, Roszko had fled his farm when bailiffs showed up to repossess his pickup truck. Police arrived on scene soon after and discovered inside the Quonset the pot farm along with stolen car parts and a stolen generator. They immediately sealed off the farm, applied for a search warrant, and began rifling through the contents of Roszko's world.

Roszko made repeated calls to his mother, who lived nearby and could report what was happening.

Her son was livid.

Roszko, former officers have since reported, loathed the RCMP. He stalked officers and their families. He accused police of harassing him, for ruining his life. Locals covertly mocked him as a child abuser and a wacko. He had weapons all over his property, neighbours whispered, and Mounties were ordered to never approach him alone.

At Hennessey's place, he demanded the .300 Winchester Magnum rifle owned by Hennessey's grandfather along with some ammunition. He was going to burn down the Quonest, he declared, thus destroying evidence. Later, he vowed to "get even" with police.

Cheeseman, who also lived in the house, gave Roszko a pillow case to wrap the gun in.

They then drove him to the field across from the Quonset, arriving sometime around 1 a.m. They could see the winking dome lights of the police cars in the distance but did nothing as Roszko grabbed the rifle and, under the cover of darkness, snuck back over the snow toward his home.

Nine hours later, Roszko -- who somehow managed to get a hold of the semi-automatic rifle and sneak back inside the Quonset -- killed the officers in a hail of bullets.

"Fear and intimidation didn't stop over the course of the evening," said DePoe. But, he stressed, Roszko's stated intention was always arson -- not murder.

So, Justice Macklin asked DePoe, if the goal was arson, why did Hennessey give him a gun?

Maybe Roszko already had matches, maybe he was going to ignite fuel tanks on the farm, DePoe replied, adding that you can't judge a man's actions when his wife and two daughters are in the next room and he's dealing with an armed and violent man.

"It's very difficult to contemplate consequences when that's occurring."

Cheeseman's lawyer, Peter Northcott, characterized his client as a social misfit and loner who looked up to Hennessey, lived in his basement and babysat his kids. So when Hennessey asked him that night to come along for moral support, he never hesitated.

When he gave the pillow case to Roszko, the gun had already been handed over, said Northcott. When they drove Roszko to the farm, Cheeseman was a passenger, nothing more.

"He's not in control. He's not connected to what Roszko's up to," said Northcott, adding he believes Cheeseman should get two to three years in jail.

The pair were arrested in July 2007 following a massive RCMP undercover operation. They spent months in jail before being granted bail. After they pleaded guilty Monday, they were ordered held in custody.

Once the cases are wrapped up, a fatality inquiry is expected to be called. In 2007, an RCMP workplace safety report recommended stronger body armour for police along with night-vision goggles and better radio communication.