A Chicago man has been in prison 20 years for murder though 6 witnesses said he didn’t do it. His lawyers allege police misconduct.

A man serving a 71-year prison sentence is seeking to have his murder conviction tossed out, in part because of allegations of misconduct by a Chicago Police officer who was once ripped by a judge for “garbage” testimony.

The recent filing by attorneys representing Antonio Porter, 48, is the latest development in a winding murder case that has seen several astonishing twists. Porter’s murder trial in 2003 featured four witnesses called by prosecutors who testified that he wasn’t the gunman, reversing prior statements to police.

No other direct testimony or evidence presented at the trial implicated Porter, but a Cook County jury nevertheless convicted him. State’s Attorney Kim Foxx’s office in 2018 rebuffed efforts by his former attorney to have Porter cleared, saying they believed he was properly convicted.

Now a new set of attorneys has filed a petition in court seeking to clear Porter’s name. Most specifically, Porter’s attorneys are highlighting problems with the case’s lead detective.

“Antonio Porter’s case is a case that just cries out,” attorney Anand Swaminathan said. “This is somebody who should’ve never been convicted. The idea that a case made entirely on eyewitness identifications ... and one says flat-out he was coerced, that’s a case where there cannot possibly be guilt beyond a reasonable doubt.”

Foxx’s office said it is reviewing the case but declined further comment.

Porter’s conviction stems from the July 2002 murder of 28-year-old Laymond Harrison. The Tribune wrote extensively about the case in 2018.

Harrison had been rolling dice with several other people outside James Madison Elementary School in Chicago’s Grand Crossing neighborhood. One of the participants, 16-year-old Vernon Andrews, later testified that the group was “drinking and smoking, sitting and gabbing.”

A man walked up and joined the game. Andrews recognized the man, whom he knew as “Black” from the Far South Side area where his mother lived, he said.

Later, the new player pulled out a handgun and stole everyone’s money. But, prosecutors said, the gunman let them know “that’s not the reason I’m here.”

“This is for Doogie,” the man declared, before firing nine bullets into Harrison.

“Doogie” referred to Robert Kizer, who was killed at a gas station a few blocks away in October 2001 while reportedly with Harrison, police said.

The gunman who shot Harrison fled and ran into a waiting car. Police gave chase, but the suspect escaped after a pursuing officer’s car engine stalled.

A witness, Giovanni Turnipseed, told police the shooter was tall and skinny. He’d watched the shooting from across the street and saw the gunman pick up cash as he made his getaway.

Police received information that Andrews knew the gunman and sought him out, but investigators weren’t able to talk with the teenager until weeks later, when he was taken into custody on suspicion of a battery.

Police arrested Andrews at 7 p.m. Aug. 28. Nine hours later, at 4:15 a.m., authorities took a statement from the teenager. From Andrews, police said they learned the shooter’s nickname, Black, and put the alias into a computer database. Cross-referencing the nickname with people in Andrews’ mother’s neighborhood, police found Porter.

Boosted by Andrews, police brought in the other dice players. Otis Burns gave a statement and identified photos of Porter as the gunman. Kenneth Brooks and Ricky Cook did the same.

Porter told the Tribune in a 2018 prison interview he was on his way to pick up wine for his mother’s birthday when police pulled him over in a traffic stop and he “never came home again.”

He said he doesn’t know anything about the shooting and didn’t know Doogie, either. An arrest report described Porter as 235 pounds and 6 feet tall.

That height conflicts with the Illinois Department of Corrections listing of 5 foot 9. His mother, Rosemary Porter, previously told the Tribune he’s 5 foot 8. When a Tribune reporter met with Porter in prison, he appeared to be about 5-foot-8 or 5-foot-9.

With several witnesses against him, Porter was in trouble, but he took his case to trial. Prosecutor Peter Goutos delivered the opening statement and promised jurors would hear from “the four people” who identified Porter as Harrison’s killer. But, Goutos warned the jury, each witness would be “reluctant” to testify.

Almost immediately, the case took a turn against prosecutors, who called Andrews as their first eyewitness.

Andrews testified that an officer threatened to choke him and slam him to the wall if he didn’t identify Porter as the gunman. Andrews, then 16, said he was held for hours without a chance to talk to his mother.

From the witness stand, Andrews repeatedly called the statement police took from him “a lie.” He declared Porter “didn’t do it.”

He said police pressured him into identifying Porter, and he gave in so he could go home.

At one point, when the prosecutor pressed Andrews to confirm his previous account given to police, Andrews responded, “I swear to God, you all crooked.”

Other witnesses also clashed with prosecutors.

Burns testified he told police in August 2002 that the gunman was a “skinny male.” Brooks testified that Porter resembled the gunman, but “that can’t be the guy.” In response, the detective told him the suspect had “gotten fatter,” Burns testified.

Cook called Harrison his “good friend” and testified that he wanted his killer brought to justice, but testified Porter wasn’t the gunman.

In Porter’s defense, attorney Benjamin Starks called to the witness stand Turnipseed and Ronald Robinson, a dice player present at the slaying who never identified Porter. Robinson testified Porter was too short to be the gunman.

During closing arguments, prosecutor James Lynch told the jury that the earlier statements taken by police have “the same weight as someone testifying in the trial before you.”

Part of Lynch’s argument focused on discrediting the prosecution’s own witnesses.

Lynch told the jury that Andrews “doesn’t like law enforcement” or the prosecutors on the case and had “no desire to testify.”

“He wanted to hide the truth from you,” Lynch said.

Starks defended Porter by saying Andrews and other witnesses were coerced into giving their statements to police.

“Now, where is the reasonable doubt? The reasonable doubt is that the people that they first got the statements from all came in here and to a man, to a man, got up and looked over and said, ‘No, I don’t see the (gunman) here,’” Starks said.

It took jurors less than 3½ hours to return a guilty verdict — a moment Porter said felt like his soul left his body.

Since then, Porter has been locked up but maintains his innocence. In 2015, prosecutors agreed to conduct DNA tests on items at the crime scene, including a pair of dice, an empty glass of Hennessy cognac and a bottle of beer. That round proved useless in assessing Porter’s case, though, because there was limited genetic material.

Then, in 2017, prosecutors agreed to another round of testing requested by a former attorney for Porter, this time on three $5 bills left at the scene. The prosecutors and Porter received the findings from a private lab’s testing that showed Porter was excluded on all DNA results, which included the victim plus a mixture of three other unidentified individuals.

Prosecutors rejected those findings as inconclusive.

Porter’s lawyers have also petitioned Illinois Gov. J.B. Pritzker for clemency but the Illinois Prisoner Review Board has not yet made a decision.

In the latest filing, Porter’s attorneys said they found a new witness who was riding his bike in the area when the shooting occurred.

“He confirms the shooter was tally and skinny, with a lighter complexion,” Porter’s lawyers wrote. Another man claims to have received a confession from an alternative suspect.

But the new filing focuses on Brian Johnson, a detective on the case who denied any investigative misconduct at trial. “Johnson assured the jury that Andrews’ statement in police custody was voluntary and reliable, and not the result of any threats or police misconduct,” the filing notes.

Events since then cast doubt on Johnson’s credibility, Porter’s lawyers argue. Specifically, Johnson was criticized by Cook County judge James Obbish for “garbage” testimony in the case of Princeton Williamson, a man who was shot in 2014 by a Chicago police officer.

Johnson questioned Williamson at his hospital bedside, and later testified that Williamson was alert and didn’t appear to be in pain as he talked openly about what led to his shooting.

But two nurses gave dramatically different accounts than the detective, saying Williamson was in no condition to be interviewed because of a painful open stomach incision that required a continuous intravenous feed of morphine.

Obbish expressed doubts that any confession was given at all, saying from the bench, “I have to seriously question whether Mr. Williamson ever did anything but maybe grunt or even knew who he was talking to.”

Obbish appeared particularly disturbed that Johnson never documented in his 32-page police report which doctors or nurses he had obtained approval from to talk to Williamson twice yet made it a point to detail who denied permission on another attempt.

“That’s one of the biggest pieces of garbage I ever heard from a professional member of law enforcement,” Obbish said, as previously reported by the Tribune.

Johnson’s disciplinary history also includes a 1998 complaint alleging he pulled a man from his vehicle, pushed him to the ground and punched and kicked him numerous times, according to the lawsuit. The Chicago Police Department’s Office of Professional Standards, which used to handle excessive force complaints, concluded that “the evidence garnered in this investigation clearly indicate that complainant was maltreated during his arrest, sustaining various injuries.”

Reached by a Tribune reporter, Johnson declined to comment.

“This officer’s credibility was the most important aspect of the state’s case against Antonio Porter and when you find out his credibility has been dismissed by a judge, that’s a game changer,” Swaminathan said.

gpratt@chicagotribune.com