in Soviet law, a person who, in cases provided for by law, takes part in an investigatory act for the purposes of attesting to the fact, content, and results of the act. The presence of an investigatory witness is mandatory, for example, during a search, view, investigatory experiment, or presentation for identification. The person conducting the criminal investigation invites at least two disinterested adult citizens who are able to understand and relate what happens correctly to serve as investigatory witnesses. Before the investigatory act begins, the rights and obligations provided for by criminal procedural law (art. 135 of the Code of Criminal Procedure of the RSFSR) are explained to the witnesses: the right to make remarks on acts to be included in the report and the obligation not to divulge information obtained from the preliminary investigation. Investigatory witnesses may be questioned on the circumstances of the investigatory action; they do not take part in court actions.