In the paper authors pay attention to existing in a criminal action dualism, manifesting itself in distinction of attorney–client confidential privilege and bar confidential privilege, standing in the position of absolute and indiscrete character of legal professional privilege. Such a thesis derive from the rules governing the legal structure of the advocacy and from principles of professional ethics. With regard to the trial procedures of examination and search both theoretical and practical aspects of legal professional privilege are emphasized, including the obligations of members of the advocacy arising from it.