Section 515(a) in Police Regulations, Bengal , 1943
(a)It is important that police officers of all ranks should be acquainted with the appearance of criminals not only of their own hut of other jurisdictions and Superintendents of Police should, therefore, insist upon all officers, who may be present at headquarters, attending jail parades subject to the proviso that the number of police officers forming the parade party does not exceed 20. Constables also should be included in these parades. Under the rules in the Bengal Jail Code no member of the police jail party shall be permitted to hold any communication with a prisoner except such as is necessary for the purpose of identification. These parades, however, will afford police officers an opportunity of recognising old offenders and of acquainting themselves with the personal appearance of prisoners, particularly unidentified prisoners and prisoners about to be released, and will further furnish indication to officers possessed of intelligence and the faculty of observation as to what prisoners are likely to give information, if interviewed.
