Extended answer:
To enter these departments, you need to take the civil service examination. Frankly speaking, I did the best in the exam.
First of all, the Commission for Discipline Inspection and the Political and Legal Committee are party member people, so it is difficult to get in. Generally, it is rarely directly taken out for recruitment. As far as the political and legal system is concerned, it mainly includes the Political and Legal Committee and the Public Prosecution and Law Department. The Political and Legal Committee has the right to coordinate the relationship between political and legal departments.
Secondly, the courts and procuratorates are required to pass the national judicial examination, because the courts are judicial organs and the procuratorates are legal supervision organs, and the requirements for the legal profession are very high.
Then there are the Judicial Bureau and the judicial administrative organs, which have relatively low requirements for the legal profession, because they have no judicial power in the traditional sense and mainly exercise administrative power.
Finally, the public security bureau, which is my personal understanding, although the recruitment conditions are relaxed now, people with relevant knowledge of criminal investigation are more qualified. Of course, secretarial, financial and other occupations are needed to see if there is any recruitment.