The Maryland Court of Special Appeals on Monday agreed to send Syed's case back to a lower court so that he can file a request to reopen the case.
That's important because Syed's legal team wants the lower court, the Baltimore City Circuit Court, to consider an affidavit by a witness who gives him a potential alibi.
The account of that witness, Asia McClain, was one of the issues raised by "Serial," a 12-episode series
that examined in detail the case of Syed, who was convicted in 2000 of killing his ex-girlfriend Hae Min Lee.
McClain's version of events could eventually be key in the judges' decision whether or not to grant Syed a retrial.
Questions over defense attorney's actions
Lee and Syed were seniors at Woodlawn High School in Baltimore County when she disappeared in January 1999. Her body was discovered in a city forest three weeks later.
Among the puzzles surrounding the case that the podcast dug into was why McClain's account that she was with Syed in the library at the time of the killing didn't make it into the defense case. She says her attempts to relay this potentially crucial evidence to his lawyer fell on deaf ears.
Syed has argued that his trial attorney, Cristina Gutierrez, made a series of missteps on his case, including the failure to speak to McClain and later to seek a plea deal for him despite his request for her to do so.
McClain filed an affidavit in January indicating that she'd be willing to testify. She said that an assistant state's attorney involved in the case had discouraged her from attending Syed's original post-conviction hearings in 2012.
'Really happy and excited'
Syed's legal team wants the circuit court to carry out additional fact-finding on the issue of McClain's account, which it hasn't previously considered.
"We get to go back into post-conviction, like we did three years ago, basically bring in Asia and the court can then decide if the attorney messed up by not bringing in the alibi witness," Syed's attorney and family friend Rabia Chaudry told CNN affiliate WBAL
The circuit court still has to decide whether to reopen the post-conviction proceedings. But Syed is pleased with the appeal court's order, according to his brother, Yusuf, who spoke to him Monday.
"He was really happy and excited, especially since the court said it was in the interest of justice," Yusuf Syed told WBAL.