The client must sign the power of attorney. After signing, if the client is not in the custody place, the client shall sign the power of attorney for confirmation. If the client is in custody, after the first meeting with the client, the client should also sign the power of attorney to confirm that he agrees to the entrustment of the client to the lawyer and further confirm the entrustment relationship.
Relevant laws and regulations:
Article 96 of the Criminal Procedure Law stipulates that a criminal suspect may hire a lawyer to provide him with legal advice, appeal and accusation on his behalf after being interrogated for the first time by the investigation organ or from the date when compulsory measures are taken.