A judge overturned a Missouri man's murder conviction in a case in which investigators failed to reveal that a witness was in a romantic relationship with the lead detective.

Judge Timothy Boyer on Friday overturned Lamont Campbell's conviction in the death of Lenny Gregory III, the St. Louis Post-Dispatch reported. Gregory, the son of a retired St. Louis police officer, was found shot in an SUV in south St. Louis in July 2011.

Campbell was 17 when the shooting happened. A jury failed to reach a unanimous verdict after a 2013 trial. Prosecutors tried him again in 2016 and this time won a conviction. Campbell was sentenced to life in prison with the possibility of parole.

Cambell, now 28, subsequently argued that his attorney was ineffective.

A witness identification expert, Jennifer Dysart, testified to Boyer in spring 2022 that the witness' accounts were unreliable due to poor lighting the night of the shooting. Two witnesses were married, allowing them to compare their stories, and descriptions of the shooter's height varied, Dysart said.

The ex-wife of lead detective Jeff Hyatt testified that she learned in 2017 her husband was having an affair with one witness. Text messages showed the affair had been going on since at least July 2016, before Campbell's trial. Boyer wrote that the relationship should have been disclosed to the defense.

Mary Fox, who represented Campbell at trial and now leads the state public defender’s office, told the judge that she could have done more to investigate the possibility of another perpetrator. She said she learned after the trial that a neighbor saw multiple people fighting with Gregory the night he was killed.

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