Rules of Court
Section 1. Preliminary investigation defined; when required. - Preliminary investigation is an inquiry or proceeding to determine whether there is sufficient ground to engender a well-founded belief that a crime has been committed and the respondent is probably guilty thereof, and should be held for trial.
Except as provided in section 7 of this Rule, a preliminary investigation is required to be conducted before the filing of a complaint or information for an offense where the penalty prescribed by law is at least four (4) years, two (2) months and one (1) day without regard to the fine. (1a)