Does it constitute a crime for lawyers of both sides to collude with each other to deceive the parties?

Lawyers of both sides collude with each other to deceive the parties, collect evidence and complain to the Bar Association or the Judicial Bureau.

People's Republic of China (PRC) Lawyers Law

Article 49 If a lawyer commits any of the following acts, the judicial administrative department of the people's government at the municipal level or municipality directly under the Central Government with districts shall give him a punishment of stopping practicing for more than six months but less than one year, and may also impose a fine of less than 50,000 yuan; Illegal income, confiscate the illegal income; If the circumstances are serious, the judicial administrative department of the people's government of a province, autonomous region or municipality directly under the Central Government shall revoke his lawyer's practice certificate; If the case constitutes a crime, criminal responsibility shall be investigated according to law:

(5) accepting property or other benefits from the other party, and maliciously colluding with the other party or a third party to infringe upon the rights and interests of the client;

If a lawyer is subject to criminal punishment for intentional crime, the judicial administrative department of the people's government of a province, autonomous region or municipality directly under the Central Government shall revoke his lawyer's practice certificate.