Dressed in costume like an Old Western cowboy, Scott Panetti -- decked out in everything from a wide-brimmed hat to boots with spurs -- attempted to subpoena Jesus Christ and President John F. Kennedy during his 1995 capital murder trial for killing his parents-in-law, a legal proceeding that trial witnesses have glumly said was nothing short of a three-ring circus.

Some lawyers and physicians who witnessed the scene in the Texas courtroom later said the trial was a joke, pointing out it was clearly unjust to allow a man with an extensive history of mental illness to act as his own counsel in a first-degree murder trial. But the state of Texas didn’t agree, and Panetti was sentenced to death.

“He did a terrible thing, but he was sick,” Yvonne Panetti, the defendant’s mother, told the Milwaukee Journal Sentinel in 2003. “Where is the compassion? Is this the best our society can do?"

At least five men with recorded histories of mental incompetence have faced execution in the last year, according to the Death Penalty Information Center. This term, the U.S. Supreme Court heard two cases regarding the habeas corpus proceedings of mentally ill death row inmates, a narrower issue that will nonetheless set a new precedent on whether a defendant’s mental competence is critical to providing effective legal representation.

The U.S. Supreme Court in Ford v. Wainright ruled that the execution of “the insane” -- or someone who does not understand the reason or reality of the punishment -- qualifies as cruel and unusual punishment.

But the decision left each state on its own to determine a prisoner’s sanity. As a result, some states (like Florida) have continued to set execution dates for individuals like the one who identified himself as the “Prince of God,” arguing that a death row inmate’s ability to simply understand that they are on trial is enough to demonstrate mental competence.

“There’s a correlation between people who commit the worst crimes and mental illness,” said Richard Dieter, the executive director of the Death Penalty Information Center. “Normal people just don’t typically commit these really strange killings, serial killings, of defenseless people.”

In the last year, inmates such as John Ferguson, Florida’s “Prince of God;” Oklahoma inmate Gary Allen;  and Ohio inmate Abdul Awkal had their imminent executions stayed after they were deemed too mentally incompetent to receive the face penalty. But just like Panetti, who to this day remains on death row, all of those men could still face lethal injection if a court eventually rules that their competence has been restored.

The National Association of Mental Health has estimated that 5 to 10 percent of inmates on death row suffer from a serious mental illness, defined as “medical conditions that disrupt a person's thinking, feeling, mood, ability to relate to others and daily functioning,” including schizophrenia, bipolar disorder, post traumatic stress disorder and borderline personality disorder.

“The question is: Is this as a society the way we want to respond to mental illness?” asked Denny LeBoeuf, the director of the American Civil Liberties Union’s Capital Punishment Project, arguing that it is not enough for a defendant to simply say they understand they will be sentenced to death.

“If someone’s talking about getting burgers after their execution, then they obviously cannot comprehend the reality of what is occurring, “ LoBoeuf said, referring to the case of one Virginia man who said he planned on going to Burger King after his death sentence was carried out.

The American Bar Association and American Psychiatric Association have called for a moratorium on the execution of the mentally disabled, which the United Nations Human Rights Commission describes as a human rights violation. But while the execution of individuals with mental retardation (typically someone with an IQ of less than 70) has also been outlawed by the nation’s high court, those suffering from a range of mind-altering and often untreated mental illnesses are not protected.

“Does it include depression? Does it include alcoholism? Momentary despair? Or does it only apply to a few high-level diagnoses? And how can you prove a defendant was mentally ill at the time of the crime?” Dieter said, who believes that current laws don’t specify what degree of illness is necessary for a defendant to be considered mentally incompetent.

“If everyone who had some kind of mental illness was exempted, there would probably be very few people left on death row,” Dieter said. “And states are a long way away from letting that happen.”

Case in point: On Election Day, California voters rejected a ballot referendum that would have abolished the death penalty and replaced it with life imprisonment without the possibility of parole. Supporters focused on the fiscal benefits of outlawing capital punishment in a state with a bloated prison population, with one report estimating that implementing the death penalty in the state costs $184 million more per year than limiting maximum punishment to life without parole.

Thirty-three states currently authorize the death penalty. Texas, which overwhelmingly leads the nation in executions, has put 492 prisoners to death since 1976.

Connecticut, the only state that ever specifically exempted the mentally ill from execution, completely abolished the death penalty earlier this year.

While the Supreme Court’s upcoming decision will not settle whether it is legally or morally permissible to execute the mentally ill, Dieter said it could be the first step toward seeing the court consider the issue in a comprehensive manner.

“The court has taken on age, retardation and insanity when it comes to capital punishment, but not the big question of mental illness,” he said.