DENVER – More information was released Thursday on how a clerical error led to the wrongful jailing of a Denver man.

Shawnnon Hale, 24, was released Wednesday. Police said his DNA was improperly identified by a lab technician as being tied to a sexual assault that happened in July. A later test found his DNA was at the scene but wasn't tied to the assault. DPD arrested Hale in December.

"The DNA match is correct. The CODIS (DNA database) system worked," Denver DA Mitch Morrissey said. "It was the clerical error that led us to believe that the DNA match was to a different item of evidence.

Hale's DNA was found at the scene of the alleged rape, but it didn't match the DNA in the rape kit.

Hale doesn't deny he was at the 4th of July party, but he said he didn't sexually assault anyone.

"This happened the next day. It was at 12 a.m.; that's when I left," he told 9NEWS Wednesday. "I left with a group of friends. They showed in the video that I left with a group of friends."

According to 9NEWS sources, Hale's DNA was found on a cigarette butt. It matched his DNA in the DNA database, CODIS. DNA samples are marked with letters and numbers. Sources tell 9NEWS, an analyst writing the report for a detective inadvertently swapped the numbers. He should've said the DNA from the cigarette butt matched Hale, but instead he said the DNA from the rape kit matched him.

"No one wants to see and spend a day in jail unjustly," DPD spokesperson Sonny Jackson said. "We don't ever want that to happen to anyone. This was a clerical error. This is not a system failure by any means."

Hale's DNA was in the CODIS system because he's a convicted felon with a criminal history. He's been arrested by Denver, Aurora and Colorado Springs police, as well as the Arapahoe County Sheriff's Office. Charges include receipt of stolen property and a number of property crimes.

DPD says this error doesn't call into question other DNA cases the crime lab works on or the work of this analyst.

"What it shows is that we have checks and balances in place to address problems when they come up," Jackson said. "Obviously, we caught this through our checks and balances system."

Now, DPD has two investigations on their hands: a sex assault and an internal inquiry.

"The one thing you should take away from this is that we do have some stop gaps in place, and we did address the problem," Jackson said. "We're going to address any issues that we have."

Just last year, the Denver Crime Lab worked on 796 cases that had multiple pieces of DNA. This is the first reported mistake.

The DNA analyst in question has been with the Denver Crime Lab for more than six years.

Hail said he plans to sue the department.

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