Why you should avoid eating in a restaurant according to contraversy Anthony Bourdain?

The late celebrity chef and author Anthony Bourdain once wrote that you should avoid eating in a restaurant with a dirty toilet because, if they let you see the bathroom looking like that, imagine what their unseen workspace and kitchen might look like.

I think what you might call the “Bourdain principle” applies to public policy, too. States have really complicated functions and it is hard to assess their effectiveness day-to-day. As a result, we tend to use metrics that are relatively easy to measure.

The UK’s four-hour waiting target in hospital accident and emergency departments is a good example of this: there is no particular medical misfortune that becomes more likely at four hours and one minute, but it’s a useful way to assess the overall health and performance of the British healthcare system. Similarly, we expect an awful lot more of schools than that they turn out graduates who are literate and numerate, but literacy and numeracy are good “Bourdain principles” for the overall effectiveness of the system.

In criminal justice, the principle applies best to police stops. Imagine you have a population of 100 people, the vast majority of whom will never commit any form of crime. But within the population, there are some with criminal intent.

You can make only a limited number of searches because you don’t have infinite resource. The game is to find and charge as many crooks as possible while avoiding inconveniencing the innocent. Your effectiveness in police stops isn’t a perfect guide to the overall health of your criminal justice system. But it is one of the easiest parts to measure.

What unites all these things is that the ideal number is zero. The ideal number of pupils who leave compulsory education without being literate or numerate is zero. The ideal number of patients waiting in hospital for more than four hours is zero. And the ideal number of innocent people who undergo a police stop is zero. But the crucial difference is that the achievable number of all three things isn’t. 

The UK used to meet its four-hour waiting target in A&E. Most states in the rich world manage to turn out high-school graduates who are both literate and numerate, other than in exceptional circumstances. But in criminal justice, you can’t get away from what the criminologist Richard Berk describes as the “Darth Vader/Luke Skywalker problem”: you can either design your criminal justice system to maximise the chances of catching the guilty Darth Vader or to do as much as you can to avoid capturing the innocent Luke Skywalker.

To make matters worse, whichever you choose to prioritise, you still won’t always get things right. Punitive approaches will punish the innocent but still miss the guilty from time to time. Lenient ones will spare the guilty while ensnaring the innocent.

Politicians of all stripes struggle with policy in areas where the desirable aim is zero but the achievable aim isn’t. Often in criminal justice, the solution is simply to pretend that the trade-off doesn’t exist.

In New York under mayor Michael Bloomberg, for instance, the percentage of unsuccessful stop-and-frisks (that is, the number of searches that ended without some form of sanction or other) was never lower than 80 per cent and was sometimes as high as 90 per cent. The overwhelming majority of people stopped by police under Bloomberg had done nothing wrong and almost certainly shouldn’t have been searched.

Under Bill de Blasio, the number of stops fell dramatically. But so, too, did the number of arrests. Bloomberg pursued a “Darth Vader” approach: but the NYPD was no more effective at finding the guilty at the end of his mayoralty than it was at the beginning. De Blasio pursued a “Luke Skywalker” approach, but the police became much less effective at catching wrongdoing and protecting the innocent as a result.

Neither mayor could be said to have acknowledged the trade-offs involved in their respective approaches. Nor did they seek to learn from cities such as London, where the number of stops not resulting in further police action hovers consistently around the 70 per cent mark.

In areas where the achievable aim is more than zero, politics is often stuck — between either pretending that you can achieve perfection through the right set of policies, or assuming that what we have now is the best policymakers can hope for. Part of the solution is for politicians to find ways to be realistic without becoming fatalistic. The other is for media and civil society to let policymakers speak frankly about trade-offs.