Manuel Pardo was a decorated Florida police officer before he was fired for lying and turned to life as a vigilante, slaying nine people during a three-month crime spree.

Almost 27 years later, Pardo, 56, is scheduled to be executed Tuesday night. U.S. Judge Timothy Corrigan denied Pardo's request for a stay on Monday.

Most of Pardo's victims were involved with drugs, officials said, and Pardo contended that he was doing the world a favor by killing them.

"I am a soldier, I accomplished my mission and I humbly ask you to give me the glory of ending my life and not send me to spend the rest of my days in state prison," the then-31-year-old Pardo told jurors at his 1988 trial.

Pardo's attorneys are trying to block his execution, arguing in federal appeals that he is mentally ill, something his trial attorney believed more than two decades ago.

"I think that anyone who would get up and ask a jury sentence him to death is insane," lawyer Ronald Guralnick said recently.

Regino Musa, the brother of one of Pardo's victims, said it's difficult to grasp that the execution will finally happen. He and his elderly mother plan to attend.

"It's about time. It's been so long, you just want to get it over with," said Musa, whose sister, Sara Musa, was killed by Pardo. "I still have nightmares and I don't have words to describe it. I can't believe that it's happening."

Pardo, a former Boy Scout and Navy veteran, began his law enforcement career in the 1970s with the Florida Highway Patrol, graduating at the top of his class at the academy. But he was fired from that agency in 1979 for falsifying traffic tickets. He was soon hired by the police department in Sweetwater, a small city in Miami-Dade County.

In 1981, Pardo was one of four Sweetwater officers charged with brutality, but the cases were dismissed.

In 1982, The Miami Herald reported that Pardo saved a 2-month-old boy's life by reviving him with CPR. Another story, written by famed South Florida columnist and novelist Carl Hiassen, noted that Pardo arrested a man for stealing valuable parrots and cockatoos to use as live sacrifices for a Santeria ritual.

He was fired four years later after he flew to the Bahamas to testify at the trial of a Sweetwater colleague who was accused of drug smuggling. Pardo lied, telling the court they were international undercover agents.

Then over a 92-day period in early 1986, Pardo committed a series of robberies, killing six men and three women. He took photos of the victims and recounted some details in his diary, which was found along with newspaper clippings about the murders. Pardo was linked to the killings after using credit cards stolen from the victims.

He had become fascinated with Adolf Hitler, collecting Nazi memorabilia. His dog, a Doberman pinscher, had a swastika tattoo.

"He was very cold," retired prosecutor David Waksman told the Herald recently. "He was doing robberies and went home and slept like a baby. He was proud of what he did."

One victim was a confidential informant who sold Pardo guns. Others, like Musa's sister, were just in the wrong place at the wrong time.

Guralnick thought Pardo was insane and tried to use that as a defense, arguing he couldn't tell right from wrong.

Over Guralnick's objections, Pardo insisted on testifying at his trial, telling jurors that he enjoyed killing people and wished he could have murdered more.

"They're parasites and they're leeches, and they have no right to be alive," he said in court. "Somebody had to kill these people."

Guralnick said his client was not only a rigid, military-loving man, but also a product of the lawless, cocaine cowboys-fueled zeitgeist of 1980s Miami.

"I'm not admitting that he did any of that, but let's say he did," said Guralnick. "He was a victim of the time. The people he was dealing with were trash."

In a news conference following his conviction, Pardo said that instead of choosing to model himself after Hitler, he could have idolized Martin Luther King Jr. or John F. Kennedy.

"But they were pacifists," he said. "I'm an activist."

While on death row, Pardo placed ads in tabloid newspapers, looking for pen pals. He eventually corresponded with dozens of women and convinced many to send him money through the mail, collecting $3,500. Pardo was dubbed the "Death Row Romeo."

Guralnick said that Pardo was a "guy's guy" and that as an officer, he did some commendable things.

"You can do something wrong and do a lot of right things, too," said Guralnick.