Th is paper examines the formalization of the investigation from the perspective of criminal proceedings.Firstly, and in order to accomplish this, it gives a brief account of the discussion about the meaning of the object and takes position about this.It then analyzes the right to know the contents of the complaint.Both aspects can generate a basis for examining the formalization of the investigation, its characteristics and control mechanisms.Finally, it theorizes about the nature of the 'reformalización' and new formalizations of the investigation that can be carried out in a process, analyzing the objections that have been made, for alleged violations of rights of the accused with such acts, concluding that these acts are adjusted to law, which respond to the characteristics of the object of the process in the investigation stage, and that the problems are really found in the way the closure of the investigation is regulated.