Justice Ketanji Brown Jackson, in her first opinion since taking office over the summer, objected Monday to the Supreme Court’s decision not side with an Ohio death row inmate’s claim.

Jackson, joined by fellow liberal Justice Sonia Sotomayor, said the court should have ruled for Davel Chinn, who was convicted of a 1989 murder in Dayton during a robbery. Instead, the court rejected Chinn’s appeal.

Chinn’s lawyers argued that prosecutors had withheld evidence that a key witness, Marvin Washington, was severely mentally disabled, with an IQ of 48. Washington had identified Chinn as the shooter.

Jackson wrote in an opinion dissenting from the court’s decision to reject Chinn’s claim that there was “no dispute” that the state had suppressed evidence that would have undermined Washington’s credibility as a witness. Under a 1963 Supreme Court ruling called Brady v. Maryland, such conduct can constitute a due process violation.

Jackson took issue with a February ruling by the Cincinnati-based 6th U.S. Circuit Court of Appeals in the state’s favor, which she said failed to properly analyze whether the evidence about Washington affected the outcome at trial.

“Because Chinn’s life is on the line, and given the substantial likelihood that the suppressed records would have changed the court at trial … I would summarily reverse,” Jackson wrote.

Jackson, the first Black woman to serve on the Supreme Court, was appointed by President Joe Biden to replace fellow liberal Justice Stephen Breyer, who retired over the summer.