He was released on April 15, four months earlier than he was meant to have been freed, on what the governor's order described as "special-needs parole" - an attempt to avoid an outbreak of coronavirus in the Colorado prison where he was being held.
"The potential spread of Covid-19 in … prisons poses a significant threat to prisoners and staff who work in facilities and prisons, as well as the communities to which incarcerated persons will return," Polis said in the order, signed at the end of March.
"In making those decisions they are taking into consideration the safety of prison guards and others," the governor said.
"But no person who is a danger to society should be released early in any situation and of course nobody on that parole board thought that this person was going to do what they allegedly did."
Haney had been eligible for parole since 2017 and was set to be released on August 22.
"They couldn't have held that person much longer than they did," Polis said.
According to local media, he was in prison for felony robbery.
"Haney was released due to special-needs parole criteria," Annie Skinner, a spokeswoman for the Department of Corrections, said in a statement.
READ MORE:
• Covid 19 coronavirus: US turning on its top expert, Dr Anthony Fauci
• Covid 19 coronavirus: US and China tensions soar after Trump trade threat
• Covid 19 coronavirus: Are New York's improving numbers masking the true trajectory of US outbreak?
• Covid 19 coronavirus: First United States patient revealed
"When looking at special-needs parole criteria, the Department of Corrections' medical staff reviews offenders for risk factors related to Covid as documented by the Centres for Disease Control. The clinical team reviews the inmate's medical records to individually confirm the existence of conditions and their severity. The department also reviews information related to their crime of incarceration and behavior inside the facility."
"Nobody should be released simply because of Covid-19. Of course the parole board, in making individual evaluations, [has] a tough job that they do," Polis said.
Haney is being held in the downtown Denver jail without bond, and facing 14 counts, including possession of a weapon by a previous offender, unlawful possession of a controlled substance, theft and attempted second-degree kidnapping, as well as first-degree murder.
Authorities linked him to the killing using surveillance footage taken by police cameras. He was later found in a nearby motel bathroom.