i think i read something similar on reddit years back. someone was arrested and everything was in japanese and he couldn't read anything. the police and lawyers were asking him to plead guilty or something and he was adamant on a lawyer which he never got. he was in jail for months i think.
If I remember correctly, police in Japan can hold you without a lawyer for 21 days, and then renew the detention more or less indefinitely.
I hope that they didn't try to claim their Miranda or fifth amendment rights.
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