Adnan Syed, who was convicted of murdering his ex-girlfriend Hae Min Lee in 1999 and whose story featured in the 2014 podcast Serial, has been told he will not now get a retrial.
The Court of Appeals of Maryland, the state’s highest court, on Friday overruled an earlier decision.
Syed’s lawyer, Justin Brown, said the case could now go to federal courts.
The case for a retrial centres on an alibi witness who was not called in the original trial.
The hit podcast suggested the evidence it had unearthed from Asia McClain could have corroborated Syed’s account that he was in the library when his ex-girlfriend was killed.
But judges said that her not being there did not prejudice the trial. They did however say that Syed’s original legal team was “deficient”.
The decision was carried with four judges against three.
Syed had been granted a new trial in June 2016 but the state appealed against it. First the appeal was rejected but now it has been upheld.
Syed’s lawyer told the Baltimore Sun newspaper that there were “at least three other avenues of relief” and said on Twitter that Syed would keep trying to clear his name.
The Adnan Syed case was carried in the first season of the Serial podcast, with its 12 episodes being downloaded 175 million times.
The US cable TV channel HBO will shortly air a documentary series called The Case Against Adnan Syed.