Under the heading"Certiorari Denied," Nathan Dunlap, known as the Chuck E. Cheese killer, lost his death penalty appeal before the U.S. Supreme Court on Tuesday, according to Denver Post.

Dunlap, the longest-serving death row inmate, Nathan Dunlap, lost, what the Denver Post stated was the "last, best chance to avoid execution" for the murders of three teenagers and a 50-year-old mother of two in 1993.

It all started in July of 1993 when after being fired from his cooking job at the Chuck E. Cheese in Aurona Colo., Nathan Dunlap hid in the bathroom on Dec. 14, until closing and then emerged and shot employees Sylvia Crowell, Colleen O'Connor, Bobby Stephens, Marge Kohlberg and Ben Grant.

Being tried and convicted, in Feb. 1996, on four counts of capital murder as well as other crimes. Later that year, he was sentenced to death on the murder counts and consecutive terms totaling 113 years in prison on the other counts, according to Yahoo.

Upon hearing the verdict, Dunlap and his lawyer went to work trying to appeal the sentence.

Denver Post reports that Dunlap argued before the Supreme Court and, later, the Court of Appeals that his trial council was ineffective in presenting evidence that he was mentally ill -- evidence which might have "mitigated his culpability enough to persuade at least one juror to vote for life imprisonment instead of death," the orders state.

Yahoo states, according to the orders, the Colorado Supreme Court found that Dunlap has said to a doctor during the evaluation, "I'm gonna play crazy as long as I can ... The police have no case against me, they're stupid."

The Denver Post reported that an attorney for Dunlap has given a statement saying that the man should serve life in prison without parole and that capital punishment in Colorado would be "unfair and disproportionate."

The 18th Judicial District Attorney will now make a motion in Arapahoe County District Court for the judge to issue a death warrant, the Denver Post reported, with the warrant specifying a week during which the execution should be carried out and the Colorado Department of Corrections selecting the day.

7News in Denver reports that since the state reinstated the death penalty in 1976, only one person has been executed -- Gary Lee Davis in 1997. Dunlap is one of three men currently on Colorado's death row.