A motorist refused to help the victim of a mugging. As the motorist drove away, the victim broke off the exhaust purifier of his 20th century petrol-burning car. Judge Dredd arrived on the scene moments later, killing all three muggers. The victim informed Dredd of the motorist who left him to die, gave the judge enough of a description for Dredd to track down the motorist. Dredd caught up with the motorist and found that he had no criminal record, but used a pollution meter to find that, as the exhaust purifier had been broken off, the car was now in violation of Mega-City One's pollution laws and destroyed it.