Former President Yoon Suk Yeol is in court to attend a hearing on his habeas corpus petition, amid a special counsel investigation into his martial law move in December.

Yoon arrived at the Seoul Central District Court around 9 a.m. Friday for the 10:15 a.m. hearing to review the legality of his detention.

Within 24 hours of the end of the hearing, the court must decide whether to release Yoon or keep him behind bars.

Yoon’s defense team reportedly argued that the former president is already indicted without detention on the five charges the special prosecution team listed on its pretrial detention warrant, meaning he cannot be detained over the same allegations.

The special counsel team is scheduled to present its argument in the afternoon. 

Yoon, who was taken back into custody last week, is expected to personally appeal for his release by explaining how his health has deteriorated recently.

The previous day, Yoon’s lawyers told reporters that the former president, who is taking medication for diabetes, spends most of his time lying down in his cell and has difficulty eating and exercising.

While the team is challenging Yoon’s detention on procedural and substantive grounds, it said the former president wants to discuss his health directly with the justice. 

The special counsel team plans to assert that the former president’s detention is lawful and remains necessary.