Section 84 - Practice before the commissioner; immunity of witness1. All hearings before the commissioner, or an officer or employee of the department specially authorized to conduct an investigation or hearing, shall be governed by rules to be adopted and prescribed by the commissioner. And in all investigations, inquiries or hearings the commissioner, or an officer or employee of the department specially authorized to conduct an investigation or hearing, shall not be bound by the technical rules of evidence.2. In any investigation or inquiry by or upon any hearing before the commissioner, or an officer or employee of the department specially authorized to conduct an investigation or hearing, the commissioner, or the officer or employee conducting the investigation or hearing, may confer immunity in accordance with the provisions of section six hundred nineteen-c of the code of criminal procedure.