A jury sentenced a man to life in prison Wednesday for his role in a series of random nighttime shootings that unnerved metropolitan Phoenix in 2005 and 2006.

Samuel Dieteman, who pleaded guilty to two of six murders in the Serial Shooter case and could have been sentenced to death, appeared stoic as the jury's decision was announced. His lawyer put his arm around him.

Asked by the judge if he had anything to say after the sentencing, the 33-year-old Dieteman looked down and said he couldn't think of anything. Then he said, "I'm truly sorry for the pain that I've caused to many, many people."

Authorities say Dieteman and his former roommate preyed on pedestrians, bicyclists and animals in attacks that ended in August 2006 when both men were arrested at the apartment they shared in Mesa.

Paul Patrick, a victim of the shooting spree who nearly died when he was shot while walking down a street in June 2006, was in the court for the verdict and said he agreed with it.

"It's not a cause to celebrate; a mother just lost a son, and children lost their father," he said of Dieteman's family. "No hatred for the family. Too much time has been wasted on that."

Dieteman, who had been charged with murdering two people and attacking 14 others, had admitted to fatally shooting 20-year-old Claudia Gutierrez-Cruz in Scottsdale in May 2006 and assisting in the deadly shooting of 22-year-old Robin Blasnek in July 2006 as she walked from her parents' home to her boyfriend's house in Mesa.

Prosecutors had argued against a life sentence for Dieteman. His lawyers asked jurors to consider his testimony as a key witness against his former roommate, 36-year-old Dale Hausner, who received six death sentences earlier this year. Dieteman and Hausner met in April 2006 — about nine months after the Serial Shooter attacks began.

Testimony at Dieteman's sentencing trial included a written apology from Dieteman to a victim in which he said he would make "no cries for mercy." He also said he regretted his actions, including not turning in Hausner to authorities when he first learned of the shootings.

"There's so many things I would change back then," he told jurors.

Dieteman's attorneys had argued that making Dieteman spend the rest of his life behind bars would be punishment enough. While Hausner's attorneys had accused Dieteman of giving bad information to avoid the death penalty, Dieteman said he wanted to help punish Hausner.

Prosecutors, on the other hand, called Dieteman's cooperation too little, too late. They painted him as a drifter who was a willing participant, pulling the trigger and serving as Hausner's lookout.

Investigators said their big break came when one of Dieteman's drinking buddies, Ron Horton, called police to say that Dieteman had bragged about shooting people. "They called it 'RV'ing.' Random Recreational Violence," Horton told The Associated Press in a 2006 interview. Horton died last year.

During Hausner's trial, Dieteman said Hausner professed a hatred for prostitutes and homeless people as they looked for victims in areas frequented by streetwalkers. Dieteman said Hausner never explained why he wanted to shoot people.

In describing one shooting, Dieteman said he and Hausner found humor at the sight of one of their seriously injured victims, who held his stomach and appeared angry.

Dieteman previously told jurors that he and Hausner often followed news accounts of the killings because they wanted to see which leads investigators were pursuing.

In late March, Hausner was given six death penalties and hundreds of years in prison for killing six people and attacking 19 others. Hausner has denied any involvement in the attacks and suggested Dieteman might have carried out some of the crimes.

Dieteman also was a witness in a case against Hausner's brother. Jeff Hausner was sentenced in June to 18 years in prison in the 2006 stabbing of a man in a church parking lot. Authorities say the assault was linked to the Serial Shooter attacks.

Dieteman testified that he and Jeff and Dale Hausner were driving around that night when they spotted Timothy Davenport as the man was walking in west Phoenix. Davenport was slashed in the face and stabbed twice, according to court documents. He survived after being hospitalized.