New South Wales Consolidated Acts New South Wales Consolidated Acts(cf Police Powers (Vehicles) Act 1998 , s 11)
(1) A roadblock authorisation may be given either verbally (including by telephone, radio or other communication device) or in writing (including facsimile).
(2) A roadblock authorisation has effect for a period of 6 hours (or such lesser period as may be specified by the senior police officer giving the authorisation).
(3) Nothing in this section prevents a senior police officer from giving a further roadblock authorisation in respect of the same vehicle (or class of vehicles) on a road, road related area or other public place or school.