A Maryland appeals court on Tuesday reinstated Adnan Syed's murder conviction after finding that a lower court violated the victim's family the right to attend a hearing on vacating the conviction.
Syed, the subject of the "Serial" podcast, had his conviction tossed out by a circuit court and the Baltimore County state attorney's office dropped charges before he was set free last fall.
Syed, who is now 41, had been serving a life sentence for the past 23 years -- more than half his life -- since his arrest in 1999.
He was just 17 when he was convicted of first-degree murder, robbery, kidnapping and imprisonment of his ex-girlfriend, Hae Min Lee, in 2000.
He has maintained his innocence and denied any involvement in Lee's death.
An appellate court panel voted 2-1 to reinstate the conviction, according to a court filing.
"We vacate the circuit court's order vacating Mr. Syed's convictions, which results in the reinstatement of the original convictions and sentence," the court filing said. "We remand for a new, legally compliant, and transparent hearing on the motion to vacate, where Mr. Lee is given notice of the hearing that is sufficient to allow him to attend in person, evidence supporting the motion to vacate is presented, and the court states its reasons in support of its decision."
Judge Michelle Phinn ordered Syed's release in October 2022, asking for his shackles to be removed after listening to the state and the defense make arguments.
She said that "in the interests of fairness and justice," Syed should be released on his own recognizance after finding that prosecutors failed to turn over evidence that could have helped his trial in 2000 and after new evidence was discovered that could have affected the outcome of his case.
The appellate court said "the circuit court violated Mr. Lee's right to notice of, and his right to attend, the hearing on the State's motion to vacate."
A spokesperson for the state attorney said in a statement the office is "conducting a review of the decision." The office did not answer whether Syed has to return to prison.
"We must allow the appeals process to play itself out, Mr. Syed and his legal team may file for an appeal to the Maryland Supreme Court, and we must respect their rights to do so until those rights are either heard or that request is denied; we are in a holding pattern. Any further comment would be premature at this time," said spokesman James E. Bentley II.
Syed's attorney issued a statement to ABC News saying that as of right now, Syed remains a free man.
Syed's attorney Erica Suter said she plans to appeal the decision to reinstate Syed's conviction to the state's highest court.
She says Syed and his team remain optimistic that justice will be done.
ABC News' Quinn Owen contributed to this report.