By Tori Mason

DENVER (CBS4)– Four Colorado families found justice this week thanks to DNA technology. The man responsible for killing four women decades ago has been identified. He was arrested in the ’80s for the death of a female police officer, then killed himself in jail shortly after. No one knew of the families he destroyed before that day.

Joe Ervin in 1981 (credit: CBS)

Our reporters spoke to the witness of that officer’s murder 40 years ago. That witness spoke to CBS4 again on Friday.

In 1981, Glenn Spies came to the aid of a now fallen Aurora Police officer. He had no idea how dangerous the man he confronted was until now.

Spies says he was working for the Police Explorer Program in Aurora. He describes it as a program for young people interested in law enforcement to see if they want to police as a career.

“We would go to the police station and grab a radio and travel to the parks, making sure everything was safe. We’d go to the pools to see if they needed anything. We’d just kind of walk around to make sure there’s no graffiti or anything like that,” explained Spies.

On June 27, 1981 Spies was driving home from his shift when he saw an arrest turn violent.

Aurora Patrolwoman Debra Corr was conducting a traffic stop.

“I pulled behind her car. I got out and tried to assist the officer at which time I heard her scream for help. I heard gunfire and tried to duck behind the patrol unit,” said Spies. “He shot me and I fell to the ground.”

Before shooting Spies, Joe Michael Ervin shot and killed Corr with her own weapon.

Glenn Spies (credit: CBS)

Corr was a 26-year-old one-year veteran of the Aurora Police Department. That night, she became the first APD officer killed in the line of duty.

Spies was wounded, but he survived.

“I heard him run to his car and take off,” Spies recalled. “I tried to get up and move but I couldn’t. I laid there in the middle of the street until help came. To me, it seemed like forever, but it was probably about two or three minutes.”

CBS4 archive footage shows him speaking to reporters from his hospital bed 40 years ago.

“She looked like she was having a rough time. She was struggling with him, so I thought I’d get out and help,” said 19-year-old Spies.

Spies didn’t know until Friday that four other women needed saving, too.

“I got the calls this morning. It was kind of a shock because I didn’t know he had more victims,” said Spies. “Now the people that have been affected by it can be at rest.”

Debra Sue Corr (credit: Aurora Police)

DNA confirms Corr wasn’t Ervin’s first victim – she was his last.

We now know he’s responsible for the deaths of multiple women. Their families finally have closure.

While Irvin didn’t take Spies’ life, he took away a young man’s dream of joining the department. That night has stayed with him for as long as the shattered bullet near his spine.

“They’re saying I’m lucky to be walking because of the damage I have to the spine and the nerve that goes to my left leg. I’m in more pain than I used to be,” said Spies.

Though he struggles to walk, Spies has strength for forgiveness.

There’s nothing the once young hero would take back.

“That’s a part of me. I love to help people out and I would do it again,” said Spies.

Technology is allowing more and more Colorado families to finally get answers and find closure. There’s no telling how many more cold cases will be solved in the coming years thanks to it.

Tori Mason