John Mathis Watson, 68, was transported to a mental-health facility in Nevada where he will be treated until he is ruled competent to stand trial, according to documents from the Clark County Courthouse.
"So that's what happens ... everything just stops because that's the law," the judge said in court documents. "And, you know, if he cooperates up there, maybe he'll come back in six weeks, and we can reset this. If he doesn't cooperate up there, he might not come back for six or eight months, and then we'll reset."
Upon hearing the ruling, Watson spoke up in court.
"It's -- here's the problem -- I have a question. I did not know illness -- it's not a mental illness," Watson is documented as saying.
Prosecutors say Watson shot his 50-year-old wife, Everilda Watson, during a vacation in Las Vegas, then cut her body into pieces with an electric saw he bought at a home improvement store.
A grand jury in Clark County indicted Watson on murder, kidnapping and robbery charges.
Prosecutors were seeking the death penalty in the trial.
Watson was sent to the Lakes Crossing mental-health facility on Oct. 30.
During the investigation, detectives found a large amount of blood in the couple's Jeep and in a Las Vegas hotel room that Watson reportedly rented using a false identity and a disguise.
There is also evidence that Watson bought an electric saw, bleach, incense and odor-absorbing trash bags at the time, authorities said. A tarp with the woman's blood on it reportedly was found in a remote area of Tulare County. The material matched the tarp found in the back of Watson's car, authorities said.
Watson, however, insists he did not murder his wife. Earlier this year, he told reporters his wife got mad at him in Las Vegas and stormed away after learning he had been keeping several secrets from her, including his cancer diagnosis.
Now, the public may never know what happened to Everilda Watson.
"As you know, the defense has raised the competency issue of Mr. Watson, and Mr. Watson, whether it be a ploy or not, has refused to cooperate with the doctors, so there's no (way) I can make a finding that he's competent and go forward," a judge said in court documents.
Staff Writer Rod Leveque contributed to this report.