DENVER (AP/CBS4) — A man charged with murder in the shooting death of a Denver police officer at an outdoor concert last summer pleaded guilty to a lesser charge Friday.

Rollin Oliver pleaded guilty to second-degree murder and faces at least 16 years in prison when he is sentenced at a hearing scheduled for June 21.

Oliver, now 22, was accused of fatally shooting officer Celena Hollis when he fired into a crowd at a jazz concert in City Park last June. His attorneys said he was being pursued by gang members when he drew his weapon and fired.

Prosecutors dropped a charge of first-degree murder with extreme indifference for human life in exchange for Oliver’s guilty plea.

“This was a difficult decision for the family and the office of the district attorney. We made this decision today with the family’s understanding,” prosecutor Tim Twining said.

“Over the course of the last many months they’ve spent a lot of time in discussion, in preparation for a trial, in talking with the family,” Lynn Kimbrough with the district attorney’s office said. “Through those discussions and through their work on the case the decision was made to seek a negotiated guilty plea to second-degree murder.”

Investigators say Hollis, 32, was rushing to break up a fight when she was killed.

Hollis was a single mother raising a daughter and had been a Detroit police officer before she joined the Denver Police Department in 2005. She also served as president of the Denver Police Department Black Police Officers Organization.

Officer Celena Hollis (credit: Denver Police)

Officer Celena Hollis (credit: Denver Police)

A fellow Denver officer said Hollis’ parents and sister lived in Denver, and Hollis was happy to come to the city, which she considered safer than Detroit.

“This is a case we know that has touched a lot of lives and will have an impact for quite some time — not just on her family and the community, but the police department and the law enforcement community,” Kimbrough said.

A 5-kilometer run and walk was held at City Park last Sunday in Hollis’ memory. Her family created a community outreach organization called the Celena Hollis Foundation.

LINK: Celena Hollis Memorial Fund

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