Section 4(1) in The Departmental Inquiries (Enforcement Of Attendance Of Witnesses And Production Of Documents) Act, 1972
(1)Where the Central Government is of opinion that for the purposes of any departmental inquiry it is necessary to summon as witnesses, or call for any document from, any class or category of persons, it may, by notification in the Official Gazette; authorise the inquiring authority to exercise the power specified in section 5 in relation to any person within such class or category and thereupon the inquiring authority may exercise such power at any stage of the departmental inquiry.
