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Prosecutors played a haunting audiotape of a 2005 courthouse shooting rampage that left four people dead as they launched their case against the alleged gunman Monday, while his attorneys said he was so deluded he believed he was carrying out a rebellion.

Brian Nichols could face the death penalty for the shootings of a judge, court reporter and sheriff's deputy at the Fulton County Courthouse, and a federal agent later that day. Nichols, 36, has pleaded not guilty by reason of insanity. His lawyers say he couldn't tell right from wrong.

During opening statements in Nichols' oft-delayed trial, Fulton County prosecutor Kellie Hill called him a "conniving, vicious, cold-blooded, remorseless, evil and extremely dangerous killer" who carefully planned the attack and methodically sought out his targets.

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"He's not insane," she said. "He had a plan. And we're going to bring you proof of the plan."

Prosecutors say Nichols was being escorted to a courtroom where he was being tried for rape on March 11, 2005, when he beat a deputy guarding him, stole her gun and went on a shooting spree.

As Hill played a brief audio clip of a routine court hearing interrupted by gun shots and terrified screams, Nichols sat silently, his eyes downcast. Relatives of the victims wept and Nichols' father abruptly stalked out of the courtroom.

The defense team countered that Nichols was "swallowed whole" with a belief that he was a slave rebelling against authority. While others looked at the judge with respect, Nichols saw him as an enemy, said defense attorney Henderson Hill.

"What you will see is that these delusions were real for Mr. Nichols," he said. "He believed in them as you believe that ice is cold, that night follows day. These were truisms for him."

Since Nichols' arrest three years ago, the effort to bring his case to trial has been beset by a series of complications that have alternately astonished and outraged a community trying to recover from the shootings that turned Fulton County's seat of justice into a crime scene.

Lawmakers furious at a state-funded defense bill of at least $1.8 million have threatened to cut more funding to the state's public defender system. Nichols has been accused of plotting an escape. And the district attorney sued the presiding judge, who later stepped down.

The new judge, James Bodiford, has vowed to keep the case on track and brushed off an attempt by Nichols' attorneys to delay the trial again. Defense attorneys called for a mistrial after the audio clip was played, but Bodiford overruled them.

"I think we've waited long enough," Bodiford said Monday. "And I think both sides are in good shape, so I don't worry about any issues about lawyers being ready."

The judge also admonished an alternate juror who wrote a letter asking to be excused for "emotional" and "mental" reasons. Bodiford said the man, whom he compared to a soldier deserting his army, would become a "shadow juror." That means he will be expected to sit in the audience throughout the trial but will not help decide the case.

The trial, being held a few blocks from the scene of the downtown Atlanta shootings, could last months. It took nine weeks to select a jury of eight women and four men, and more than 600 witnesses could be called.

The trial began amid high security. Police cordoned off streets outside the Atlanta Municipal Courthouse, guards with bomb-sniffing dogs roamed the hallways and visitors were siphoned through two separate security checkpoints.

Nichols is accused of fatally shooting Superior Court Judge Rowland Barnes and court reporter Julie Ann Brandau in the courthouse and sheriff's Deputy Hoyt Teasley just outside the building. A fourth victim, federal agent David Wilhelm, was killed at a north Atlanta home he was renovating.

In addition to the costs for Nichols' defense, the shootings have also gouged the budget for Fulton County, which is on the hook for at least $10 million in settlement fees to victims' families.

Barnes' widow won a $5.2 million lawsuit last month. And county commissioners on Wednesday agreed to pay $5 million to Brandau's daughter, Christina Scholte, who also sued.