1, the investigation stage, criminal defense lawyers provide legal assistance to criminal suspects. After the public security organs, people's procuratorates and other legal organs conducting investigation of the suspect's first interrogation or the date of compulsory measures, the law firm can accept the criminal suspect or his relatives to hire, assign a lawyer to meet with the suspect, criminal defense lawyers can provide legal advice, representation of the complaint, accusation, the suspect is detained, you can apply for a bail to await trial for the suspect. 2, At the stage of examination and prosecution, the criminal defense lawyer acts as the defender or litigation agent. Criminal case by the investigating authorities to the people's procuratorate for review and prosecution, the lawyer can accept the suspect or his friends and relatives entrusted to serve as a defender; can accept the victim and his legal representative or close relatives, civil litigants entrusted to serve as a litigation agent. In the review and prosecution stage, as a defender of the lawyer can access, excerpts, copy the case related materials, with the suspect to meet or correspondence, investigation, Peihu collection of materials related to the case, put forward the defense or representation. In the examination and prosecution stage is detained for an extended period of time, the defense lawyer has the right to request the release of the suspect or change the coercive measures in accordance with the law, the implementation of the bail pending trial. 3, the trial stage, criminal defense lawyers as a first instance, the second instance of the public prosecution of the case of the defender. At this stage, the lawyer has the right to go to the people's court to inspect, excerpt, copy the case materials, meet with the defendant in custody, according to the actual situation of the law, investigation, collection of evidence and materials related to the case, apply to the people's court to notify the witness, appraiser, investigation and examination of transcripts made by the witness, apply for re-appraisal, participate in court investigations, published defense, etc.. After the first instance verdict can meet with the defendant, listen to the content of the verdict and whether to appeal, and give legal help. 4, the trial stage, criminal defense lawyers act as the prosecutor of the case of the victim's litigation agent. The lawyer should cooperate with the public prosecutor, according to law, exercise the function of prosecution, and the defendant and his defense debate, on behalf of the victims on the conviction and sentence of legal claims. To summarize, lawyers representing criminal cases provide legal assistance to suspects in the investigation stage, examination and prosecution and trial stage. Criminal case lawyer fee standard is based on the level of local economic development, the difficulty of the case, spend time and energy, etc., generally speaking, the investigation stage of the lawyer charge assault hole fee in accordance with the standard of two thousand to six thousand. Criminal suspects have financial difficulties, can not afford, can apply for legal aid.