Maryland’s highest court has reinstated the murder conviction of Adnan Syed, who was freed after spending more than 20 years in prison fighting charges that he killed his ex-girlfriend.

The ruling marks yet another twist in the case made famous by the hit podcast Serial, as it now returns to a lower court for a new hearing.

Syed was cleared of all charges in 2022, after prosecutors said he had been wrongfully convicted of strangling and killing his ex-girlfriend Hae Min Lee.

But in March 2023, an appeals court reinstated his conviction after finding that the lower court had failed to give Young Lee, Ms Lee’s brother, sufficient notice of the hearing that freed Syed.

In a 4-3 opinion, Maryland’s Supreme Court on Friday upheld this decision, saying the lower court judge had “worked an injustice” by not giving Young Lee reasonable notice of the hearing.

The ruling means the case will be sent to a lower court for a new hearing on whether Syed’s murder conviction should be thrown out. The court did not order any changes to his release, meaning he will remain free while his case is heard.

In a statement, Syed’s lawyer, Erica Suter, said the court had reached a decision his legal team “could not disagree with more”.

“The highest court’s decision may be final but that does not make its reasoning right,” Ms Suter said.

“Though this latest ruling is a roadblock in the way of Adnan’s exoneration, we have faith that justice will prevail, and will work tirelessly to clear his name once and for all,” she added.

Syed and Hae Min Lee were classmates in high school in Baltimore County, Maryland when Lee disappeared in January 1999. Her body was found in a forest three weeks later.

Prosecutors at the time alleged Syed carried out the crime after becoming jealous of Lee’s new relationship after the two broke up.

Syed’s story became known to millions through NPR’s Serial podcast as well as an HBO docuseries, both of which cast doubts on the evidence linking Syed to Lee’s death.

The investigations have alleged prosecutors relied on inconsistent testimony from a classmate of Syed’s as well as unreliable cell phone tower data to place him at the scene of the crime.

The Lee family has continued to argue that Syed is guilty and has opposed his release.

Hae Min Lee’s brother, Young Lee, said in 2022 that he wished to travel from California to attend the hearing that freed Syed, but he could not on short notice.

Syed’s lawyer, Ms Suter, has argued Young Lee’s rights were not violated as he was allowed to participate in the hearing via video.

“This isn’t a podcast for me. It’s real life,” Young Lee told the court during the 2022 hearing.