THERESA MAY, the Conservative home secretary, does not usually come across as a liberal. In her speech to the Conservative Party conference on September 30th, her main announcement was a tough new plan to deport illegal immigrants before they are allowed to appeal. But Mrs May is also now pursuing a more liberal cause. “Stop-and-search is crucial in the daily fight against crime”, she said. But, she added, “we cannot ignore public concern about whether it’s used fairly”.

Police stop-and-search has long been controversial. In the 1980s Victorian “sus” laws allowed police to search suspects on thin pretexts. This was blamed partly for causing riots in inner-city areas such as Brixton, in south London, and Handsworth, in Birmingham. “It was out of order”, says Chris Donaldson, a recently retired black Metropolitan Police inspector, who reckons that things have improved drastically since. Unfair stops were also cited as evidence of institutional racism in the Met in the 1999 Macpherson report.

Today, searches are more controlled—they must be recorded and usually require a specific reason to suspect the person searched. But for much of the past decade, the number of such interventions was mounting fast, boosted by searches under counter-terrorism legislation and by drugs searches. In 2012, police conducted 1.2m searches, up from around 820,000 in 2004 (see chart)—a figure which excludes traffic stops and stops without searches. The most frequent criticism is that black people are six times more likely to be searched than white people. This is often overemphasised. Britain’s inner-cities, where most searches take place, are not as white as Britain at large, Mr Donaldson says. But that black people are stopped more often even in many rural areas is unsettling. The process can be distressing. Dami Benbow, a black 22-year-old politics student from Lewisham, in south east London, says that when he was stopped, he felt that the officers who searched him were unnecessarily rough. It is also not clear that stop-and-search reduces crime. A report published in July by Her Majesty’s Inspectorate of Constabulary (HMIC), the police regulator, found that the power is often used erratically. Just 9% of searches result in an arrest, while around perhaps a quarter may not properly comply with the law, because of poor recording or insufficient grounds. Another recent academic report noted that around 50% of searches are conducted on suspicion of drugs offences, yet while the number of drugs searches has climbed dramatically since 2002, the number of arrests that result has fallen, from 43,900 to 39,400. Police forces are changing their approach however. Counter-terrorism searches have been all but stopped, while some of the other sorts are becoming less common. A culture change may be under way in the police too. “The intention of cops is to do it right,” says superintendent Rick Burgess of West Midlands Police. But poor training and technology—many searches are still recorded on carbon-paper forms—lead to errors. The West Midlands Police, like other forces, is retraining its officers and adopting new technology: GPS trackers and digital records submitted by radio. It is even experimenting with using body-mounted cameras to record stops—something Mr Burgess reckons will reduce complaints.

Better technology and training might well reassure both police and the people they stop. While young black men may resent being searched, police officers also worry about being accused of racism. Reform might benefit the Conservative Party too, suggests Simon Woolley, the director of Operation Black Vote, a pressure group. Many ethnic-minority voters are still suspicious of police power, he says. Some feel let down by the Labour Party, which allowed the number of searches to escalate while in power. The Conservative Party desperately needs to win more of them over. If Mr Woolley is right, then Mrs May’s new stroke of liberalism may prove shrewd as well as humane.