The Port of Portland Police are a body of special constables attested under section 79 of the Harbours, Docks, and Piers Clauses Act 1847 (as incorporated by Portland Harbour Revision Order 1997). They were established in 1997 when the Portland Harbour Authority Ltd. bought the port from the British Government. The act uses the term 'special constable'; at the time this act was passed 'special constable' meant any constable who was not a member of a territorial police force
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Port of Portland Police (United Kingdom) Wikipedia(Text) CC BY-SA