UPDATED: 10/12/10 10:09 p.m.

JOLIET, Ill. (CBS) – Murder charges were dropped against a Lynwood police officer accused of a deadly two-state shooting spree.

Brian Dorian had pleaded not guilty to first-degree murder in Will County court earlier Tuesday. He had been charged in the shooting death of Rolando Alonso, 45, last week. Police have said the man who shot and killed Alonso at a construction site in rural Beecher in Will County also shot and critically wounded 19-year-old Joshua Garza at the scene, and then later shot and injured 62-year-old farmer Keith Dahl in Lowell, Ind.

On Tuesday evening, Dorian was brought to the Will County Sheriff Department’s investigations division in Joliet with his attorneys, Bob Odekirk and Dave Carlson.

They met with prosecutors and investigators, who were able to verify that Dorian was using his computer until at least 11 a.m. the day of the shootings, Odekirk said. The first shooting occurred about 10:30 a.m. on Oct. 5.

Sheriff Paul Kaupas and State’s Attorney James Glasgow held a press conference to announce the news.

“Based on the evidence that we have developed today, it would’ve been physically impossible for Brian Dorian to have committed this crime,” said Glasgow.

“Physically impossible” because further examination of Dorian’s home computer clears him.

“Late this afternoon, we received some computer forensic information that places Brian Dorian in his home at the time of the Beecher shootings,” said Glasgow.

But Kristina Garza, the aunt of 19-year-old Joshua Garza injured in the Beecher shooting, told CBS 2’s Suzanne Le Mignot, she is doubtful about Dorian’s computer alibi.

“My computer here in my office is on 24-7. And it’s my username, my password, but my assistant uses it. And I don’t even touch it. But if you were to look at it, it would appear that Kristina Garza is on the computer 24-7. So I’m not satisfied with that explanation,” said Garza.

Garza is hoping her nephew Joshua, who is still in the hospital recovering from the shooting, can identify the shooter.

“If he says this is not the person, then Brian Dorian got the justice that he hoped for,” said Garza. “But if Joshua, on the other hand, says he’s absolutely 100 percent convinced, then Brian Dorian needs to hire civil counsel because we will pursue a civil lawsuit immediately. Because I will go to hell and back to support Joshua – absolutely.”

Glasgow offered Dorian no apology Tuesday night, saying the other evidence investigators had, including a witness who saw the shooting in Beecher, pointed to Dorian.

“If you look at all of the evidence that pointed towards him, it’s uncanny,” said Glasgow. “In this particular case, I guess Brian Dorian can thank god for computer technology.”

At one point though, Glasgow and Kaupas seemed to be at odds over just how strong their case was.

“We were on the fence on this case. We were letting the evidence take us where we were supposed to go, and we had questions in our own mind,” said Kaupas.

“When we charged this case, we were not on the fence,” said Glasgow. “In addition to the positive identification of a living eyewitness who watched the shootings happen, we also had a description of the truck that matched.”

Still tonight, they conceded they charged the wrong guy and hoped Dorian would understand.

“This is a terribly tragic case. I feel horrible that Brian Dorian went through this. I certainly would apologize for any inconvenience that he has suffered,” said Glasgow. “But at the same time, he is a police officer, and if he were in our shoes, and he had a suspect under these circumstances, Brian Dorian would have acted the same way.”

Right from the start, Brian Dorian’s father told CBS 2 that authorities had the wrong man in custody, and his son was innocent. Tonight, John Dorian says he’s relieved his son is finally being released. But he’s also angry.

“For a policeman to be put in jail and being innocent, emotionally it takes a lot out of you,” said John Dorian, Brian’s father. “There’s a miscarriage of justice, a defamation of character and false arrest.”

The Lynwood Police Department issued the following statement Tuesday night: “Officer Dorian’s reputation has been damaged, and his family and fellow officers have been dragged through the mud.”

Shooting victim Rolando Alonso’s sister-in-law, Laura Gonzalez, reacted to news of Dorian’s release by phone Tuesday night.

“We cannot believe they caught the wrong guy. They stopped looking and now this guy is gone. We thought they had the right guy but now we’re scared now what’s going to happen. Now this guy can hurt someone else,” Gonzalez told CBS 2.

This is not the first time the Will County Sheriff’s Department has been the subject of scrutiny. Earlier this year, a man was charged for the 2004 murder of 3-year-old Riley Fox. Scott Wayne Eby was charged after evidence that had been overlooked for years came to light.

Initially, five months after Riley’s murder, her father, Kevin Fox, was arrested by Will County Sheriff’s police on murder charges.

Authorities said at the time that Fox told investigators he decided to make his daughter’s death look like an abduction after he thought he accidentally killed her by hitting her in the head with a door.

But Fox claimed detectives coerced him into saying he had hit Riley’s head, accidentally causing her death.

Fox was charged with her rape and murder, and spent eight months in jail before DNA testing — obtained by his own defense team — proved he did not sexually assault Riley.

He was released on June 17, 2005, and the case went unsolved for nearly five years.

“They’re just astounded,” said Fox family attorney Kathleen Zellner in June. “He’s extremely angry. For him, to realize he could have died on death row and this is what they were doing with the evidence, it’s pretty hard to wrap your mind around it.”

A judge approved a personal recognizance bond, freeing Brian Dorian Tuesday night. He will return to court Wednesday at 9 a.m. so charges can officially be dropped.

While the news is good for Dorian and his many supporters, it comes with bad news for residents: The man responsible for the shooting spree is still on the loose.

CBS 2’s Jim Williams, Suzanne Le Mignot and the Sun-Times Media Wire contributed to this report.

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