A triple-murder trial in Red Deer heard new details Thursday about the complicated relationship between two men accused in the December 2013 killings of a Castor-area farm family.

Jason Klaus and Joshua Frank are each charged with three counts of first-degree murder in the deaths of Klaus's parents and sister. Police believe Gordon, Sandra and Monica Klaus were shot in the head before the family's farmhouse was set ablaze to destroy evidence.

Klaus and Frank were arrested for the killings in August 2014.

In Court of Queen's Bench Thursday, Klaus was grilled by Frank's defence lawyer Tonii Roulston as she tried to tear apart his story piece by piece.

She suggested Klaus was the only one responsible for the deaths of his parents and sister.

"I'm suggesting you are the one who went into that farmhouse and shot your sister, your mom, your father and your dog," Roulston said.  "Not Mr. Frank. You."

In a calm voice Klaus responded, "No. I completely disagree with you."

"Then you started the fire to cover up your actions," she continued.

"No, that is not true," he answered.

The 41-year old continued to insist Frank shot his family without his knowledge. He said he only found out about it days after the murders.

Klaus said he lived in fear because Frank threatened to shoot him or a member of his family if he told anyone about it.

But despite his supposed fear, Klaus continued to have contact with Frank.

Love triangle and jealousy

The month after his family was killed, Klaus got a new girlfriend, Amanda. She worked at the hotel bar in Castor where Frank rented an upstairs room.  

Klaus admitted rumours swirled in the small town that Amanda was having sexual relations with Frank.

"On one occasion I approached Josh in late January," Klaus testified. "I believe it could have been in the bar. I remember asking him if these rumours were true. If he was having sex with Amanda."

Cosmopolitan Hotel

Cosmopolitan Hotel in Castor, Alberta where Joshua Frank rented a room and the two accused often frequented. (commercialrealestatealberta.ca)

He said Frank confirmed the rumours.

"Were you angry that Mr. Frank was sleeping with your girlfriend while you were dating her?" Roulston asked.

"I didn't know if he was telling me this to brag about it or if he was telling the truth," said Klaus.

"I trusted Amanda. So I couldn't see it being true."

Klaus said the rumours refused to go away so he said he confronted Frank a "couple more times."

"Either you're scared of him or you're not scared of him," Roulston persisted. "I'm suggesting you're not scared of Mr. Frank."

Threats in wiretapped phone calls

Roulston played three phone calls intercepted by the RCMP. They were made by Klaus to his girlfriend on March 9, 2014. During those calls he said he was angry with Frank for spreading rumours about Amanda.

"When I see Josh it's not going to be pretty," Klaus told Amanda.

"I'm going to start cracking heads. He's a pain in my ass. I don't care if I get a f--king assault charge."

Later the same day, Klaus placed another call to Amanda to let her know he'd sent Frank a  "very, very threatening nasty text," and that Frank was going to visit him on the farm.

"I'm going to be having a chat," Klaus told her.

"If I get in trouble, I get in trouble."

On the witness stand, Klaus testified, "I'm not a violent person. That was just talk to Amanda. But I had no intentions of following up on that."

The defence lawyer questioned Klaus's priorities.

"You're not mad enough to send a nasty text or have words with him about killing your family?" she asked rhetorically.

Allegations of sexual assault

Frank is nine years younger than Klaus. Klaus said he began to sell cocaine to Frank and use it with him when Frank was in his early 20s.

Roulston challenged that assertion.

"You spent some time with Mr. Frank when he was between 14 and 17," Roulston said. "Would you agree with that?"

"I would say that is not true," Klaus answered.

"Was there any sort of sex that you had with Mr. Frank when he was 14 years old?"

Showing no reaction, Klaus answered, "No, there was not."

Joshua Frank

Joshua Frank being questioned by Mr. Big in an undercover RCMP operation. (RCMP )

Roulston suggested Klaus had sexually assaulted Frank and would hit Frank and slap him if he refused to comply with his sexual demands.

As Frank cried in the prisoner's box, Klaus calmly answered on the witness stand, "No, that's not true."

Secret meeting

By June, 2014, Klaus was deeply immersed in an RCMP Mr. Big sting.

On June 3, Klaus confessed to an undercover officer for the first time. He said he didn't shoot his parents and sister, but paid Frank to do it.

In cross-examination Thursday, Klaus admitted he met with Frank a few days after he made that confession. The two men met up at a campsite 11 kilometres east of Castor.

"I'd suggest at that time you relayed details of your parents' murder to Mr. Frank," Roulston said.

"I'll suggest you asked Mr. Frank to relay that information to Mr. Big. You wanted him to say it was him who committed the murders."

Klaus denied the suggestions.

Roulston also suggested Klaus drew a map of the farmhouse for Frank so he could accurately describe what happened the night of the murders.

"So he could have the same details you had," she said.

"No," Klaus answered.

Klaus will be cross-examined Friday by Crown prosecutor Douglas Taylor.

Frank is expected to begin testifying in his own defence once Klaus is finished on the stand.