08/30/2012 02:45 pm ET Updated Aug 31, 2012

Alprentiss Nash, Chicago Man, Cleared Of Murder Charge After 17 Years In Prison

Updated story

A 37-year-old Chicago man who has been in prison since 1997 on a murder conviction will soon be freed thanks to new DNA testing that prosecutors say confirms they locked up the wrong man.

Alprentiss Nash was previously convicted in the 1995 slaying of Lion Stroud and sentenced to serve 80 years in prison, the Chicago Tribune reports.

Prosecutors in the case alleged that Nash was wearing a ski mask when he broke into Stroud's South Side home but had denied Nash's request that DNA testing be conducted on the mask. That testing ultimately linked another man to the crime, according to the Tribune.

Kathleen Zellner, Nash's attorney, told CBS Chicago that she expected her client will "be really surprised" by the news that he could be freed from the Menard Correctional Center as early as later Thursday.

"The first thing he wants to do is get out and see his mother and then he promised to bake a cake for me," Zellner added.

Cook County States' Attorney Anita Alvarez announced Nash's dismissed charges -- the first overturned murder conviction since the advent of her office's new Conviction Integrity Unit -- Thursday afternoon, according to NBC Chicago.

Alvarez created the new unit, aimed exclusively at investigating allegations of torture and police misconduct, in February.

"I can't tell you with certainty whether he was or wasn't involved, at this point, in the crime," Alvarez said Thursday, according to ABC Chicago. "The investigation continues, but I would tell you, if we were to retry this case now, we don't believe we could meet our burden against him, that's for sure."

Earlier this year, the National Registry of Exonerations named Illinois, and Cook County in particular, as home to the nation's highest number of documented wrongful convictions.