Prosecutors to call cousin, wife to witness stand in capital murder trial of Arizona fugitive

A key prosecution witness is expected to be called to the stand Monday as the trial of an escaped Arizona inmate accused in the grisly slayings of a husband and wife enters its fourth week.

John McCluskey is the last of three defendants to be tried on federal carjacking and murder charges in the 2010 shooting deaths of the Oklahoma couple whose bodies were found incinerated in their burned-out travel trailer on a remote ranch in eastern New Mexico.

Prosecutors said the testimony of McCluskey's cousin and wife, Casslyn Welch, could last a few days. Welch is facing life in prison after pleading guilty last year to charges stemming from the slayings of Gary and Linda Haas of Tecumseh, Okla.

Welch, McCluskey and his former prison bunkmate Tracy Province targeted the Haases on Aug. 2, 2010, while the three were on the run following a prison break that occurred just days earlier. It was Welch, prosecutors said, who helped the men escape a lockup near Kingman, Ariz., by throwing tools and weapons over the prison fence.

Weary of traveling through three states in a small getaway car without air conditioning, the trio wanted the Hasses' truck and trailer after spotting the retirees at a rest stop near the Texas-New Mexico state line.

At gunpoint, the couple was forced to drive to a lonely road off of Interstate 40. Testimony during the first three weeks of the trial indicated Province and Welch were outside the trailer when McCluskey allegedly shot the Haases. Gary Haas was shot once, Linda Haas three times.

The fugitives took the truck and trailer to a more desolate spot, unhitched the trailer and set it ablaze with the Haases' bodies inside.

Jurors have seen photographs and video of the brittle remains and the charred trailer. They have also seen the handguns and bags of ammunition seized by investigators following the arrests of McCluskey and his accomplices.

Authorities captured McCluskey and Welch at a campground in Apache County, Ariz., following a three-week nationwide manhunt.

If convicted, McCluskey would face either life in prison or the death penalty.

His defense team has implied it plans to present evidence that he has a mental defect or disease. In a notice filed earlier this month, the attorneys said they might call to the stand two neuroradiologists in addition to a forensic neuropsychologist who performed clinical tests on McCluskey. Some of the tests assess a person's planning ability and could be used to show lack of intent.