A Minnesota man was set free Monday after spending nearly two decades in prison for a wrongful murder conviction, officials said.

Hennepin County Judge William Koch signed an order Monday vacating the conviction of Marvin Haynes, ruling that the evidence used in the case was not reliable and "constitutionally improper." Haynes, 36, was convicted of murder in connection to the fatal shooting of 55-year-old Harry “Randy” Sherer in 2004.

At the time of the killing, Haynes was only 16 years old and his conviction had relied on eyewitness identification evidence. The Hennepin County Attorney’s Office said in a news release Monday that Haynes' constitutional rights were violated during his trial in 2005.

"Almost twenty years ago, a terrible injustice occurred when the state prosecuted Marvin Haynes. We inflicted harm on Mr. Haynes and his family, and also on Harry Sherer, the victim, his family, and the community," Hennepin County Attorney Mary Moriarty said during a news conference Monday. "We cannot undo the trauma experienced by those impacted by this prosecution, but today we have taken a step toward righting this wrong."

Shortly after his conviction was overturned, Haynes was released from the Minnesota Correctional Facility-Stillwater in Bayport, Minnesota. Haynes later appeared at the news conference with his family, attorneys, and Moriarty as people cheered and rejoiced over his freedom.

Haynes said he plans to visit his mother, who he hasn't seen in the last three or four years since suffering a stroke and hopes to get a job.

"I'm just appreciative to be here and people to recognize my innocence," Haynes said. "All I want to do is move forward and just get my life back... I haven’t cried so much in 19 years."

'Height of injustice':New York judge vacates two wrongful murder convictions

What happened during the 2004 shooting?

Haynes was accused of shooting Sherer in a Minneapolis flower shop during a robbery in 2004. He was convicted of first-degree murder and second-degree assault in 2005 and was sentenced to life in prison.

At the time of his conviction, Amy Klobuchar, Minnesota's senior U.S. senator, served as Hennepin County's top prosecutor.

Represented by the Great North Innocence Project, Haynes lobbied and pleaded his case before a judge. His conviction was overturned following a November hearing where Haynes’ lawyers argued that he was wrongfully convicted based on unreliable eyewitness identification and unnecessarily suggestive police lineups, according to Koch's order.

Koch also said in his order that Haynes’ attorneys showed evidence that Haynes did not match the physical description provided by the primary eyewitness. He noted that Haynes was "significantly" younger, lighter in weight, and shorter than the described assailant.

The case had "rested almost exclusively" on eyewitness identification, according to Moriarty.

"There was no forensic evidence, such as fingerprints or DNA. There was no video connecting him to the crime. The murder weapon was never recovered," Moriarty said. "That should have made any prosecutor hesitant to bring charges because eyewitness identifications are often unreliable and one of the leading causes of wrongful convictions."

'A real problem':Police misconduct settlements can cost millions, but departments rarely feel the impact

Eyewitness misidentification

Eyewitness misidentification contributes to an overwhelming majority of wrongful convictions, which are often overturned by DNA testing, according to the Innocence Project.

"Nationally, nearly 28% of exonerations involve eyewitness identification," Moriarty said. "Mr. Haynes conviction is now one of them."

The Innocence Project has identified evidence of suggestive police practices in nearly 80% of their misidentification cases. According to the Department of Justice's first national assessment of eyewitness identification standards in 2013, more than four out of five police agencies in the U.S. have no written policies for handling eyewitness identifications.

The report also revealed that 84% of police agencies reported that they had no written policy for conducting live suspect lineups, and slightly more than 64% said they had no formal standard for administering photo displays of potential suspects.

Contributing: Kevin Johnson, USA TODAY