My partner served three years in Hedong District, Tianjin, and now he has served one and a half years. What's the maximum reduction? When can I come out? I heard that it is ok to pay a fine. ...

The three-year sentence may be halved at most, and the sentence shall be counted from the date of criminal detention, which is stated in the judgment. If the fine is paid to the court of first instance, but the case of commutation is tried by the intermediate people's court where the prison is located, I suggest you go to the prison and the intermediate people's court where the prison is located to find out.