I understand that motorists have been apprehended recently for flashing their light to warn oncoming drivers of a radar camera. Some years ago Mr Charles Glendinning was taken to the High Court by the DPP after a successful appeal against a court decision, which initially convicted him of wilfully obstructing the police when he waved at other drivers to warn them of a police trap on the A303.

On 13 October 2005 Lord Justice Scott Baker and Justice Owen ruled in Glendinning's favour. Mr Justice Owen said that there was no evidence that any of the motorists warned by Glendinning had been breaking the speed limit or were about to do so. He added that some people might think that the police ought to appreciate the efforts of others to prevent speeding. Does this ruling still stand?