Chris Marshall: Stop-and-search can't be based on a hunch

So shocking are the statistics that they are difficult to even comprehend. Since the start of the year, more than 300 people have been shot in the US city of Chicago, with 53 homicides recorded as of yesterday.

A new code of practice should prevent police officers acting on "hunches". Picture: Lisa Ferguson

Sadly the figures collated by the Chicago Tribune are not atypical for a city which is in the grip of a violence epidemic and where the similar figure of 57 homicides was registered in the opening month of last year.

Back in September when he was merely an outside bet for the White House, American’s new Commander in Chief described Chicago as “out of control” and suggested a solution to the city’s rampant gun crime: stop and frisk.

Speaking in a TV interview, Donald Trump said: “I see what’s going on here, I see what’s going on in Chicago, I think stop-and-frisk. In New York City, it was so incredible, the way it worked. If (police) see a person possibly with a gun or they think may have a gun, they will see the person and they’ll look and they’ll take the gun away.”

So far, so straightforward. But as with much of what Mr Trump says, there is more to it than that.

Research carried out by the Brennan Centre, part of New York University’s law school, has found stop and frisk doesn’t actually tackle crime, quite the opposite in fact.

Research published by the independent think tank in the run-up to November’s election showed that in New York – where the number of stop and frisks peaked at 685,000 in 2011 – the murder rate fell as the number of stops declined.

Indeed, property crime and violent crime fell across the city between 2002 and 2015, a period during which the numbers of stops both increased and fell, suggesting no relationship between the two.

Later this year a new code of practice is expected to come into force in Scotland for stop and search. It will effectively ban non-statutory or “consensual” stop and search, which allows police officers to search a person simply by asking their permission.

To be clear: Scotland is not Chicago or New York.

Gun violence is thankfully rare and while there have been 53 homicides in Chicago already this year, the most recent annual Scottish figure (for the 12 months up to the end of March) was 57.

Yet there are similarities in how stop-searches disproportionately targeted certain sections of the population.

In the United States it was the black and Latino communities, in Scotland young working class males.

While the levels of violence were very different in the two countries, the outcome of police searches was the same, namely a fostering of alienation and mistrust.

Last week the Scottish Police Federation said the introduction of the new stop-search code would undermine its members, “neutering” officers and preventing them from acting on a “hunch”.

According to the SPF, the hunch is “one of the most invaluable skills a police officer has at their disposal”.

But while hunches may have led to notable arrests in the past they are undeniably based not on intelligence but preconceived notions.

As we enter a depressing “post-truth” era in politics, it’s important than when it comes to policing we deal in fact not suspicion.