In the hope that this would provide an opportunity to think about the shape of justice in the future, a mock trial event was held at the University of Tokyo using the interactive AI "ChatGPT" as a judge, and the future of the judgment attracted attention.
This event was planned mainly by students from the University of Tokyo to raise questions about whether or not complex legal decisions can be made and whether machines can accept a future in which machines judge people are judges if the judges are "machines" rather than "humans," and many people came to the Yasuda Auditorium.
The mock trial scenario assumed a fictitious case in which a woman who was harassed by her ex-dating partner, when she consulted with her current dating partner, murdered her former dating partner, and the woman was also accused of murder for conspiring to kill.
First, the clerk explained, "In this courtroom, artificial intelligence is used as judges to enhance the accuracy and speed of the trial," and the trial began.
Then, the defendant's female lawyer pleaded not guilty, saying, "The prosecution's claim that he never asked for the murder or shared the murder plan and conspired to kill the victim is completely false," and the prosecution said, "It is clear from the testimony of the defendant's friend that he intended to kill his former dating partner and conspired with his dating partner to do this." They developed each other's arguments.
During the hearing, the AI judge projected on the screen in CG also asked the witnesses questions in a synthesized voice, such as "Have you heard them propose specific plans and means for killing?"
Then, the AI judge sentenced that "the defendant is not found to be complicit in the murder crime and therefore is not guilty," and read out the reasons for the judgment, such as "It is true that the defendant had feelings of hatred, but the specific killing plan and collusion have not been conclusively proven," and the mock trial was closed.
Junichi Okamoto, a third-year law student and representative of the volunteer student group that hosted the event, said, "The aim is for each citizen living in a democratic society to think about the future form of justice as their own matter. I think it was a success in that there were people who had in-depth discussions and attracted interest. I would like to continue to deepen my studies while being exposed to the latest technology."
From an observer to the mock trial
A woman in her 40s who attended the mock trial said, "I thought that the AI judge's questions in the middle would have asked a little different questions if they were human.
Another man in his 50s said, "The result was not guilty, but I thought that if it was a human judge, I would have been guilty. Otherwise, I think that one day when I become a defendant, I will remain unconvinced until the end."
Another man in his 50s said, "I thought it would be interesting to be able to compare both human sentences and machine sentences.
The pre-sentencing questionnaire is
Just before the verdict was handed down, an online questionnaire was conducted asking those who attended the mock trial whether they were guilty or innocent, and according to the executive committee, 864 of the 559 people who responded were "innocent" and 305 were "guilty."