2. The judicial police examination belongs to the civil service examination. Usually, only two courses "Shen Lun" and "Administrative Ability Test" are tested, which requires physical fitness. Generally speaking, it is not required to pass the national judicial examination, only the undergraduate course is required to be law, and even some places do not have this requirement.
Civil servants and lawyers are obviously more demanding. As for the difficulty, we can only say that the latter is fairer.
3. The application of criminal psychology in China is mainly in the field of criminal investigation, that is, procuratorial organs and public security organs investigate criminal cases. Of course, there are research areas.