SCITUATE — The public is invited to the appointment of a new police chief, the change of command ceremony and the promotion of three other superior officers tonight.

Capt. David M. Randall will be promoted to colonel. Then, Col. William F. Mack, who is retiring as chief, will hand over command of the department to Randall.

In addition, three other superior officers will be promoted: Capt. Stephen B. Lang to major, deputy chief; Sgt. Craig W. Hawkins to lieutenant; and Patrolman First Class David G. Mack to sergeant.

The ceremony will be at 7 p.m.in the Scituate High School auditorium, 94 Trimtown Rd. A light meal will follow the ceremony.