ST LOUIS (AP) — A Missouri judge on Tuesday overturned the conviction of a man who has served nearly 28 years of a life sentence for a killing that he has always said he didn’t commit.

Lamar Johnson, 50, closed his eyes and shook his head slightly as a member of his legal team patted him on the back when Circuit Judge David Mason issued his ruling. In coming to his decision, Mason explained that there had to be “reliable evidence of actual innocence — evidence so reliable that it actually passes the standard of clear and convincing.”

Johnson walked free after he was processed out at the courthouse. Beaming, he walked up to reporters in the courthouse lobby about two hours after the ruling and thanked everyone who worked on his case, as well as the judge.

“This is unbelievable,” said Johnson, who didn’t take any questions.

St Louis Circuit Attorney Kim Gardner, who filed a motion in August seeking Johnson’s release after an investigation her office conducted with help from the Innocence Project convinced her he was telling the truth, applauded the ruling.

“Mr Lamar Johnson. Thank you. You’re free,” she said before the gathered press.

Gardner said this is a time for Johnson to spend with his attorneys and family.

“This is Valentine’s Day and this is historical,” she said.

The Republican-led state attorney general’s office fought to keep Johnson locked up. A spokeswoman for the office, Madeline Sieren, said in an email that the office will take no further action in the case. She again defended the office’s push to keep Johnson behind bars.

“As he stated when he was sworn in, Attorney General (Andrew) Bailey is committed to enforcing the laws as written,” Sieren wrote. “Our office defended the rule of law and worked to uphold the original verdict that a jury of Johnson’s peers deemed to be appropriate based on the facts presented at trial.”

Johnson’s attorneys blasted the state attorney general’s office after the hearing, saying it “never stopped claiming Lamar was guilty and was comfortable to have him languish and die in prison.”

“Yet, when this State’s highest law enforcement office could hide from a courtroom no more, it presented nothing to challenge the overwhelming body of evidence that the circuit attorney and Lamar Johnson had amassed,” they said in a statement.

Johnson plans to reconnect with his family and enjoy experiences he was denied for most of his adult life while locked up, his lawyers said.

“While today brings joy, nothing can restore all that the state stole from him. Nothing will give him back the nearly three decades he lost while separated from his daughters and family,” they said. “The evidence that proved his innocence was available at his trial, but it was kept hidden or ignored by those who saw no value in the lives of two young Black men from the South Side.”

Johnson was convicted of murder for the October 1994 killing of Marcus Boyd, who was shot to death on his front porch by two masked men. Police and prosecutors blamed the killing on a dispute over drug money. Johnson maintained his innocence from the outset, saying he was with his girlfriend miles (kilometres) away when the crime occurred.

While Johnson was convicted and sentenced to life, a second suspect, Phil Campbell, pleaded guilty to a reduced charge in exchange for a seven-year prison term.

Johnson testified at a December hearing that he was with his girlfriend on the night of the crime, except for a few minutes when he stepped outside of the home of a friend to sell drugs on a corner several blocks from where the victim was killed.

Johnson’s girlfriend at the time, Erika Barrow, testified that she was with Johnson that entire night, except for about a five-minute span when he left to make the drug sale. She said the distance between the friend’s home and Boyd’s home would have made it impossible for Johnson to get there and back in five minutes.

The case for Johnson’s release was centred around a key witness who recanted his testimony and a prison inmate who says it was he — not Johnson — who joined Campbell in the killing.