Police officers are investigating a motorist who was caught travelling at 70mph in a 30mph speed zone.
The Calderdale Special Constabulary was carrying out an operation on November 17 just before 9.30pm.
Speed checks were being conducted on Rochdale Roadd, Triangle when the dangerous piece of driving happened.
Posting on Twitter the constabulary said: "One driver thought it was acceptable to drive 40 mph over the speed limit. Enquiries ongoing."
A Special Constable holds the same powers and privileges as a regular officer and is entitled to arrest someone in exactly the same way.
Special Constable Facts - did you know?
West Yorkshire Police Specials are integrated into virtually every aspect of policing.
Special Constables do drive police cars at varying levels of competency to be able to respond to public needs, and to do so complete the same driving courses as regular police officers.
West Yorkshire Police Specials are governed by the same policies and laws as regular officers.
Special Constables are not paid, but do receive meal and mileage expenses to ensure they are not out of pocket when they turn up to perform a duty.
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