asked the Secretary of State for Scotland what are the powers available to the police in Scotland which allow them to stop vehicles at random and subsequently bring charges for minor offences; and if he will list the offences.

Only the courts can give an authoritative interpretation, but Section 159 of the Road Traffic Act 1972 appears to confer upon a constable in uniform an unqualified right to stop a motor vehicle. The constable may subsequently report to the procurator fiscal any offences that he has reason to believe have been committed.