I can't see any reason why you'd be arrested, Smowball, if you've had nothing to do with it. You're not a conspirator. Nor are you called upon to decide if other people are breaking the law. Nor are the police going to go up and down your street arresting everyone in case they "knew" about it (if they're daft enough to question anyone, just tell them what you've already said: you've got no sense of smell). Don't be one of those neighbours writing poison pen letters from behind their net curtains. Take TheChair's advice.