ALBUQUERQUE, N.M. — The slaying of an Oklahoma couple who were abducted from a New Mexico rest stop and burned after being shot to death stemmed from a lie about whether they had guns inside their travel trailer, a key prosecution witness testified Wednesday.

A defense attorney asked Casslyn Welch, the cousin and girlfriend of defendant John McCluskey, why McCluskey didn't let Gary and Linda Haas go free, as he had with a pair of truckers kidnapped shortly after McCluskey and two other inmates escaped from an Arizona prison with Welch's help.

Welch acknowledged that she told investigators shortly after her arrest that the lie about the guns had set McCluskey off.

"I've seen less set him off," Welch said in the recorded interview that the defense played for jurors.

Defense attorney Gary Mitchell grilled Welch about whether there was a conversation between McCluskey and Gary Haas inside the trailer before the couple were shot. She testified earlier this week that she heard nothing coming from inside the trailer after previously telling investigators she heard Gary Haas' voice.

Mitchell pointed to Welch's inconsistencies, saying she has established a pattern of lying to investigators and prosecutors and has tried to diminish her role in the crimes by shifting blame to McCluskey.

Mitchell also accused Welch of changing her story when it became clear she could negotiate a plea agreement with prosecutors. However, Mitchell did not challenge Welch's statements that McCluskey was the triggerman.

Welch pleaded guilty last year to carjacking resulting in death, conspiracy, use of a firearm during a violent crime and other counts. She has yet to be sentenced but could face up to life in prison.

After getting choked up, she reiterated Wednesday that taking responsibility for her role in the carjacking and slayings was "the right thing to do."

Under questioning by the defense, Welch said the plan had been to target someone with a truck and travel trailer so the trio could "get off the grid." The plan didn't involve killing anyone, she said.

The idea had been to find a remote spot far off Interstate 40 where the Haases – retirees on their way to Colorado for an annual camping trip – could be tied up and left. Welch said she and the fugitives wanted a four- to five-hour head start to get away.

The slayings occurred three days after Welch said she helped McCluskey and two other inmates escape from a privately run, medium security prison near Kingman, Ariz.

One of the inmates was caught a day later in Colorado. The search for Welch, McCluskey and his former prison bunkmate Tracy Province sparked a nationwide manhunt.

Welch also acknowledged Wednesday that she lied to federal prosecutors about her efforts to smuggle drugs into two Arizona prisons where McCluskey was housed while serving a 15-year sentence for attempted second-degree murder.

She said she smuggled the heroin and marijuana in dozens of color-coded balloons that she sometimes hid in a body cavity. She visited McCluskey every weekend and took drugs in at least once a week, she said.

The account conflicted with statements she previously made to prosecutors.

"The real reason for getting involved in bringing drugs into prison facilities is because you needed the money," Mitchell told Welch.

He then asked her again about lying to federal authorities.

"I've been protecting people all along, yes sir. That's why I lied," she said, later explaining she was afraid of what would happen to McCluskey in prison if she revealed details of the drug smuggling.

Welch said McCluskey was in charge of the operation in which he provided drugs to inmates, and their relatives or friends made payments to Welch. She also said she had drug customers outside the prisons.

She said she would deposit about $200 of the proceeds in McCluskey's inmate account each week. At first, her cut of the extra money helped pay bills but then it became a way to bankroll the escape, she said.

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