Pages 38 & 39 of Manual of the Military Police Branch, Australian Army Provost Corps 1943
The Special Investigation Branch of the Australian Army Provost Corps, consisting of experienced and trained personnel, forms part of the establishment of L.H.Q. Sections are attached to the HQ of certain Formations under the direction of the A.P.M. or D.A.P.M. of the Formation. The more serious and complicated matters of investigation will be carried out by this branch assisted when necessary by members of the Military Police Branch.
The Military Police Branch will carry out investigation of minor importance, but including those relating to desertion, absence without leave, and applications for compassionate leave.
Whenever possible experienced personnel only of the Military Police Branch should be detailed to carry out investigations, but every opportunity should be taken of attaching less experienced men to them for instruction.
Before commencing an investigation, the soldier detailed should satisfy himself that he has a full knowledge of all the available information on the case.
He should be definitely instructed as to the course his inquiries should take.
The co-operation of the civil police will be sought when dealing with civilians and any other occasion it is considered that their services may be helpful.
When the complainant specially requests the Provost Corps to act, they will do so.
Members of the Provost Corps may be called upon to assist personnel of the Intelligence Corps in security investigations.
Unauthorised investigations will not be made by the Provost Corps except when the situation is such that immediate attention is necessary. All other matters deemed to require investigation will be reported to the Officer or NCO IC of the Special Investigation Branch Section or Provost Detachment, who will act as he considers fit.
All interrogations will be made with as little publicity as possible.
Reports of investigations will be rendered promptly to the responsible A.P.M. or D.A.P.M. A copy of all reports furnished by SIB personnel will also be sent direct to the Officer IC SIB Provost Marshal Directorate , LHQ, by the Officer or NCO IC of the SIB Section concerned.