Section 16
SEC. 16. Proper use of government motor vehicles,-The use of government motor vehicles by bureaus and offices for the purposes enumerated in section 15 hereof shall be authorized only through the issuance for each trip of a serially numbered ticket duly signed by the chief or the administrative officer of the bureau or office concerned. These motor vehicles which shall be used strictly for official business shall bear government plates only and shall after office hours be kept in the garage provided therefor by the bureau or office to which they belong, except those for essential services, such as military police, experimental, mail and health service.