It is known that he was criminally detained for one month because he was wronged by the police. Can he sue the police?

You can bring a lawsuit to the people's court according to law and demand compensation. Please refer to the following legal materials:

State compensation law

Article 3 Where an administrative organ and its staff infringe upon personal rights by exercising their administrative functions and powers, the victim shall have the right to compensation:

1, illegally detaining or illegally taking administrative compulsory measures that restrict citizens' personal freedom;

2, illegal detention or other means of illegal deprivation of personal freedom of citizens;

3. Beating, maltreating or abetting or conniving others, causing bodily injury or death to citizens;

4, illegal use of weapons, police equipment, causing physical injury or death of citizens;

5. Other illegal acts that cause bodily injury or death to citizens.

Extended data:

The people's court has no right to criminal detention. The court has the right to make decisions in judicial custody, and the people's court can decide whether the parties or other people have one of the following acts according to the circumstances? Fines and detention; If the case constitutes a crime, criminal responsibility shall be investigated according to law:

(1) Forging or destroying important evidence, which hinders the people's court from hearing a case;

(2) using violence, threats or bribes to prevent witnesses from testifying or instigating, bribing or coercing others to commit perjury;

(3) Hiding, transferring, selling off or destroying the property that has been sealed up or detained, or transferring the property that has been counted and ordered to be kept;

(4) Insulting, slandering, framing, beating or retaliating against judicial personnel, participants in litigation, witnesses, translators, expert witnesses, inspectors and assisting executors;

(5) Obstructing judicial personnel from performing their duties by violence, threat or other means;

(6) Refusing to perform a legally effective judgment or ruling of the people's court. In addition to the above circumstances, there are acts of attacking the court during the court hearing, or there are other acts of obstructing the proceedings.

If the circumstances are serious, the court may decide to impose a fine of less than 1 0,000 yuan or a detention of less than10.5 days. No matter what kind of detention, the detention decided by the public security organ, the detention decided by the people's procuratorate or the judicial custody decided by the people's court shall be executed by the public security organ.

Reference: Baidu Encyclopedia-People's Republic of China (PRC) State Compensation Law