A jury has found courthouse gunman Brian Nichols guilty of murder in a 2005 shooting spree that left a judge and three others dead and turned Atlanta's seat of justice into a crime scene.

The jury deliberated for 12 hours before finding 36-year-old Brian Nichols guilty Friday of fatally shooting Superior Court Judge Rowland Barnes and court reporter Julie Ann Brandau in the Fulton County courthouse and sheriff's Deputy Hoyt Teasley just outside the building.

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A fourth victim, federal agent David Wilhelm, was killed at a north Atlanta home he was renovating.

Nichols confessed to the killings. But he pleaded not guilty by reason of insanity. He claimed he was gripped by a delusional compulsion that he was a slave rebelling against authority. The jury agreed.

Nichols sat silently as the verdicts were read about 3 p.m. EDT.

He could face the death penalty.

The 12 jurors had several options as they moved into their second day of deliberations on Friday — convicting or exonerating him, finding him not guilty by reason of insanity or guilty but mentally ill. The last option, which is rare in Georgia's judicial system, would require the prison system to evaluate Nichols and determine a punishment.

During the six-week trial, Nichols attorneys and a psychologist say phone conversations while he was in jail were evidence of his delusions. A psychiatrist who testified for the state said he found Nichols was mentally ill although he would not diagnose him as delusional.

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 started his shooting spree. He then evaded the hundreds of police on his trail, fleeing to suburban Gwinnett County.

He was captured a day later after a woman he took hostage, Ashley Smith Robinson, alerted police of his whereabouts.

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