1. After a lawyer is involved in a criminal case, he can go to the case-handling organ to learn more about the case, consult the case file, meet the criminal suspect or defendant in custody, listen to the defendant's statement of the case face to face, judge the nature of the case, and defend the defendant fully and feasible, which is impossible for family members.
2, the lawyer's intervention, in the case of not violating the prohibitive provisions of the law and the lawyer's practice discipline, can also provide a communication bridge for the families in custody and the defendant. In judicial practice, after many defendants are detained, their family life can't function normally and their families can't see themselves because they don't know the password of the passbook, where the documents are stored and the contact information of relatives and friends.
3, lawyers involved in criminal cases, can effectively help the court find out the truth of the case. Because defense lawyers are allowed to fully participate in criminal proceedings, present evidence, opinions and propositions, and effectively refute the evidence, opinions and propositions of the prosecution, the court can listen to both the opinions of the prosecution and the voices of the defense, so as to ensure that the truth can be ascertained to the maximum extent and that the defendant can get a fair trial. Urge the exercisers of public power to correct their mistakes in time, strictly abide by the procedures prescribed by law, and prevent innocent people from being wronged to the maximum extent. It can be said that the existence of defenders can indirectly promote the realization of judicial justice.
4, lawyers involved in criminal cases, can find evidence and plot in favor of the defendant, can achieve the most just punishment for the defendant.