SALT LAKE CITY — Condemned killer Ron Lafferty is competent to take part in the federal review of his conviction and death sentence, a judge ruled Thursday.

U.S. District Judge Dee Benson concluded that Lafferty, 71, does not suffer from a mental illness or defect that makes him incompetent. He has the ability to understand the nature and consequences of the court proceedings, and the ability to assist his counsel if he chooses to do so, Benson wrote.

Lafferty has exhausted his appeals in state court and wants a federal judge to overturn his conviction and stop his execution.

Lafferty's attorney requested a competency determination for Lafferty in 2009. They argued that mental health evaluations show he is not able to rationally communicate or help them. The state disagreed and believes Lafferty understands the legal process and is able to provide information necessary to litigate the case.

Both sides hired psychiatrists to evaluate Lafferty.

Benson said he found the report from the state's expert, Dr. Noel Gardner, the most persuasive and reliable.

Gardner, whose history of evaluating Lafferty goes back to the mid-1990s, found that he has a narcissistic personality and extreme religious and political views but isn't delusional or psychotic. Lafferty believes he had a special role in a pre-Earth life and sees himself as "one mighty and strong," he said.

Lafferty's sense of humor, he said, doesn't mesh with someone suffering psychosis.

"Mr. Lafferty is somebody who loves to play with words," Gardner testified at a competency hearing last October.

Lafferty, he said, has the ability to work with his attorneys but isn't willing because he sees them as "rotten snakes" and "traitors."

"I don't have the desire because I don't trust them," Gardner said Lafferty told him during one of his interviews.

A psychiatrist retained by Lafferty's attorneys, Dr. Micahael First, found that a lack of oxygen to Lafferty's brain when he hung himself in December 1984 — five months after the killings — caused cognitive and psychotic disorders. He concluded that Lafferty has delusions that "cannot be explained by his religious and extremist political belief systems."

Claiming a revelation from God, Lafferty and his brother, Dan Lafferty, slashed the throats of their sister-in-law, Brenda Lafferty, and her 15-month-old daughter, Erica, on July 24, 1984. Both men were convicted of the murders in separate trials. Dan Lafferty is serving a life sentence. Ron Lafferty was sentenced to death and chose the firing squad method.

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