Two judges rejected appeals by two men fined after being caught in the trap in Woodford, north- east London. Their lawyers said that what occurred was an illegal 'police crime-creation scheme'.
But Lord Justice Farquharson, sitting with Mr Justice Wright, said: 'This was an entirely legitimate enterprise on the part of the police and of a permissible character for the detection of crime.'
He dismissed the claim that plain-clothes Metropolitan Police officers acted as agents provocateurs by taking part in Operation Rover, a motor vehicle crime initiative in April 1992.
He said Gary Williams, 26, and his step-brother Eddie O'Hare, 23, both of Highams Park, Waltham Forest, east London, were caught trying to steal the dummy cigarettes 'because of their own criminal instincts'.
Mr Justice Wright said Williams and O'Hare, who were both fined pounds 150, acted 'in the absence of any pressure and with full understanding of their own dishonesty'.
A total of 181 people passed by the vehicle, but only Williams and O'Hare, and two boys aged about eight, showed any interest. The boys received a reprimand for removing a box from the vehicle.