Soshi was chosen to be the judge for Mazer Rackham's court-martial. On the day of the arraignment, he entered the courtroom and met prosecuting attorney Reginald Ravenshaw and defending attorney Prem Chamrajnagar. After settling in, he addressed Prem and asked if the defense wished to enter a plea, to which she said that Mazer plead as not guilty. Soshi acknowledged this, adjourning the court for three weeks. He left the room to his chambers.
The hearing for the case occurred about a week later. Soshi acquitted Mazer Rackham after Ravenshaw's only witness fell through. However, Ravenshaw decided to place a reprimand on Rackham's personal record, allowing his superiors to decide upon a suitable punishment. After Prem Chamrajnagar spoke up against Ravenshaw's decision, she was reprimanded too.
Soshi seemed to be uninterested in Mazer's case, as he appeared bored with the proceedings.