ATLANTA -- A Fulton County jury found Brian Nichols guilty Friday in the murders of four people during his escape from the Fulton County Courthouse in March 2005.

Nichols was found guilty of all 54 counts against him.

TELL US: Your Reaction To Nichols' Conviction

Nichols sat silently as the verdicts were read.

The jury deliberated for 12 hours before finding Nichols, 36, guilty 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. A fourth victim, federal agent David Wilhelm, was killed at a north Atlanta home he was renovating.

Barnes' widow was in the courtroom and wiped away tears as the verdicts were read.

"Justice was served," said Kiley Barnes, the daughter of the murdered judge.

The same jury that found Nichols guilty could recommend a death sentence for the confessed killer. The penalty portion of the trial begins on Monday morning.

Closing arguments ended Wednesday. The jury sat through six weeks of testimony that included 94 witnesses.

SLIDESHOW: Fulton County Courthouse Shooting Scene

Assistant District Attorney Clint Rucker told jurors during closing arguments that it was never a question of whether or not Nichols did it, since he had confessed.

SURVEY: Do You Agree With Nichols Verdict?

The prosecution wanted to prove that Nichols killed a judge, a court reporter, a deputy and a federal agent because he was "conniving" and "cold-blooded." "He is vicious," said Rucker.

Defense attorney Josh Moore said Nichols killed the victims because he was insane. "What this diseased mind saw was not reality. It was a distorted version of reality. The delusion in this case was that Brian Nichols was a slave," said Moore.

The state had a short response to Moore’s statement. "That is a bunch of bull," said Rucker.

SLIDESHOW: Fulton County Courthouse Shooting Victims

At the time of his escape, he was on trial for raping an ex-girlfriend.

Nichols surrendered the next day after allegedly holding a woman, Ashley Smith, hostage in her suburban Atlanta home.