In the wake of the Aurora shootings, the instinctive reaction of most Europeans is shock and bewilderment that even this latest horror does not persuade the American public and politicians of the need for gun control.

But it is usually a bad idea to draft legislation in response to dreadful pictures and appalling events. The classic example in British government is the Dangerous Dogs Act. This silly legislation was a reaction to a tabloid frenzy of 20 years ago, which claimed that a generation of children was at risk from dangerous dogs. The fiasco reached its apotheosis when Brigitte Bardot demonstrated outside Scotland’s Court of Session as its most learned judges deliberated on the fate of Woofie, a cross-breed that had barked at a postman.

After the murder of eight-year-old Sarah Payne in the summer of 2000 by a known paedophile living nearby, the newly appointed editor of the News of the World began a campaign for “Sarah’s Law”, imitating an American campaign for “Megan’s Law”. The proposal involved a register of sex offenders open to public scrutiny. The publicity reached a frenzy that summer, provoking vigilante incidents, in one of which a paediatrician returned home to find “paedo” sprayed on her house. The agitation revived after two horrific paedophile incidents in 2002 – the murder of two girls at Soham by the school caretaker, and the abduction and killing of Milly Dowler.