I agree that the quote does not apply to the law. But for some people rules are rules and "its more than my jobs worth mate" comes to mind. If the security guard smelt alchohol on the captain, he could have had a private word and told him, just like a pub landlord would say to one of his customers if they've had too much to drive. I would always advise any of my friends or colleagues not to drive if they've had too much nor to fly. What if the plane had got airborne and then crashed. Since take off to crash the security guard had told his mates that he smelt alcohol o the captains breath. Whose fault is it then?