ALLEN PARK, Mich. — A suburban Detroit man contemplated killing his former girlfriend, dismembering her body and dumping it in a body of water, an old roommate testified Monday during a preliminary hearing.

Robert Slick, 35, testified that he recalled having about 10 such conversations with Roger Bowling around 2004 while the pair drank beer and smoked marijuana. Slick said he and Bowling discussed how they'd "get rid of" the women in their lives.

Prosecutors claim Bowling killed Danielle Greenway, 32, and her fiancÚ, Chris Hall, 42, before dismembering their bodies and dumping the remains in a canal off the Detroit River.

Assistant Wayne County medical examiner Jeffrey Jentzen testified earlier that Hall was shot six times, including twice in the head. He said Greenway had been shot once – apparently through the mouth – before her head, hands and legs were sawed off and dumped in the waterway.

Bowling, 39, is charged in both slayings. The hearing, which is to decide whether there is enough evidence to order Bowling to face trial, was adjourned until Aug. 29.

For a month before Hall and Greenway were killed, Bowling had been staying as a guest in the couple's Allen Park home, west of Detroit.

"He said that he'd cut (Greenway) up, put her body in a cooler with chains ... wrap it up and dump it in the water," Slick said as Bowling stared at him Monday in Allen Park District Court.

Bowling and Slick have known each other since about first grade, Slick said. Bowling lived with him in Slick's home in 2003 and 2004.

Slick said he was going through a divorce himself at the time and Bowling was angry because Greenway was dating someone else. Greenway was not dating Hall at the time.

"We would talk about how we could get rid of our problems – get rid of our women," Slick said. "I talked about taking mine to the swamp – my wife. We'd drink beer and we'd talk about it. I didn't do it. I had the thoughts. I was very upset at that time in my life."

Hall and Greenway last were seen July 14. Authorities claim Greenway, who dated Bowling in high school, took her ex-boyfriend in as a houseguest.

Slick testified Monday that he heard about Greenway and Hall's deaths after their bodies were found. He said he thought about it for a "few days" before finally telling police about his past conversations with Bowling. "I had a conscience," Slick told the court Monday.

Slick said he believes Bowling used his father's boat to take the bodies to the east side canal, where they were dumped.

"That was the boat we used to go out on," Slick testified. "We talked about dropping bodies off in Lake Huron."

On the morning of July 17, border patrol agents spotted a torso in the canal. The U.S. Coast Guard came upon the second torso in the river while investigating the initial report. Both were beheaded.

Their hands were sawed off at the wrists, their torsos at the mid-thigh area, Jentzen testified Monday. An angler later spotted legs and a circular saw submerged near a seawall along the riverbank and not far from the canal.

"The cuts were very straight, uniform and clean," Jentzen said. "In my opinion, these would be consistent with some type of mechanical saw."

Both died of gunshot wounds, Jentzen said. Hall, in addition to the gunshot wounds to the head, was shot once in his spine, twice in his left side and once in his left arm.

Police believe the couple was shot at home.

Defense lawyer Mark L. Brown has said there was no eyewitness testimony linking Bowling to the killings.

But on July 14, a number of text messages had been sent to Greenway's cellphone from Bowling's cell, said Stan Brue, a special agent with Alcohol, Tobacco, Firearms and Explosives during testimony.

After 5:56 p.m. that day, there were no other calls or texts from Greenway's phone. A call was made from Hall's cellphone at 5:29 p.m. to a local pizza shop before it fell silent for good.

There were no incoming or outgoing calls or texts on Bowling's phone between 10:30 p.m. on July 14 through 10 a.m. on July 16, Brue said.

During an interview with detectives, Bowling said he was riding his mountain bike from about 9:45 p.m. July 14 to 5 a.m. the next day.

"I do it all the time," Bowling said in the taped interview played Monday in court. "I got on Outer Drive and started peddling."

GALLERY and Bowling's Arraignment:

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