If so, in a nutshell, criminal cases are mainly divided into several stages, namely, the public security investigation stage, the people's procuratorate review and prosecution stage and the people's court trial stage. If you want to entrust a defender in these three stages, you must go through the entrustment procedures separately and submit the entrustment procedures, letters and copies of lawyers' certificates to the corresponding case-handling organs, so that the case-handling organs can establish relations with lawyers and communicate and negotiate cases.
If the case has been decided and new criminal facts are prosecuted, it is of course necessary to go through the entrustment procedures again and submit them to the case-handling organ.
Furthermore, if an appeal is made after the judgment of the first instance, if a lawyer is to be entrusted during the second instance, the entrustment procedures must be re-handled; After the judgment of the case takes effect, if you want to get a defense, you must also go through the entrustment procedures. That is a principle: at each stage, the procedures for entrusting defenders must be handled separately.