THE streets of Hammersmith, in west London, have changed since Estela Cartwright started patrolling them in 2005. She can now spend half a day on one of the main drags without encountering any criminal activity at all: “that wouldn’t have happened when I started.” In the past two weeks there have been just two burglaries in her ward of 12,000 people.

Her experience defies expectations. Britain has been primed for crime to soar since the financial crisis struck in 2007. Conventional wisdom (plus a study by the Home Office in 1990) says that when times are tough, people steal more stuff. The police are facing swingeing budget cuts. The population is rising, especially in cities, where crime is most common. The number of men aged 15 to 24—the population most likely to offend—rose from 3.7m in 2001 to 4.2m in 2011. Youth unemployment has almost doubled since 2001; over a fifth of 16- to 24-year-olds are jobless.

And yet crime continues stubbornly to fall. Over the past 20 years it has halved in England and Wales. It is down across the West but in Britain starkly so. In America robbery and property crime have ticked up. In England and Wales crime has decreased by 8% in a single year. Vandalism is down by 14% and burglaries and vehicle crime by 11%. The murder rate is at its lowest since 1978; last year just 540 people were killed. Some less serious offences are vanishing too; antisocial behaviour has fallen from just under 4m incidents in 2007-08 to 2.4m.

Only a few crimes buck the trend. The police recorded 6% more incidents of pickpocketing in the last year, continuing a trend that began in 2008-09. The number of rapes recorded has risen, too. But that may be a good sign, because it could suggest that rape—historically a grossly under-recorded crime—is being reported to the police more often.

Why the general decline? Contrary to expectations, the lousy economy may have contributed to the drop in some crimes. Although more hands are idle, and thus available for forcing locks and breaking windows, people are also buying less, so there is comparatively little for thieves to lay their hands on. People are at home more, leaving fewer opportunities for burglars to break in undetected, suggests Siddartha Bandyopadhyay, an economist at Birmingham University. Above all, people have less money to spend on alcohol. There has been a 16% drop in consumption per head since 2004. Fewer nights on the tiles mean fewer drunken brawls. Drug use, another crime driver, is also down. And few things in homes are now worth stealing. Nobody wants pilfered microwaves or DVD players. Modern televisions are often too big to carry. Jewellery, especially gold and platinum, is still popular, as are computers, mobile phones and cash. But the old crimes simply do not pay like they used to. “Even street robbers live with their mums,” says Betsy Stanko, a professor of criminology at Royal Holloway college in London. James Treadwell, an expert on crime at Birmingham University, says that the few remaining career burglars he knows steal cannabis plants, a crime that few victims report. Central locking and immobilisers have made it harder to steal cars, turning it into a crime for the committed and skilled. In 1997 two-thirds of stolen vehicles were returned to their owners: most had been taken for joyriding. Only a third disappeared for ever. Today that ratio has reversed. The decline in vehicle crime may have driven other crime down. Nicking cars is a “debut crime”, say criminologists—a gateway to more serious offences. Cut such petty crimes and others fall too. Ms Cartwright sees the sense in this. She describes a boy who started his criminal career spitting at people and throwing eggs before progressing to bike theft and car crime. He is now in prison for drug dealing.

The police have played a part with smarter work. The West Midlands force has seen a 13% drop in crime in the last year. Chris Sims, the chief constable, says policing has become more targeted. Coppers meet daily to determine priorities. The force has invested in dealing with heavy drug users (who can commit colossal numbers of crimes), offering clinics for testing. Officers work with the probation service and the local authority on issues such as employment and housing. There and elsewhere, community policing means bobbies know their beats and the problems they face. Hammersmith’s officers report cars with valuables on display to the Driver and Vehicle Licensing Agency; that outfit contacts owners and warns them to be more careful.

The decrease in crime is beyond doubt, but Mr Treadwell cautions that the kinds of activity that are now the staple of the professional criminal, like cloning credit cards, do not show up in crime reports. The ones he interviews talk of salad days spent shoplifting cigarettes and booze and selling them on housing estates. Today they make fake designer T-shirts and flog them online, away from the police’s prying eyes. Crime on the internet is a big problem that will continue to grow, says Mr Sims. His force is encouraging people to report online crimes, not because it can react to particular incidents, but because it hopes to pick out patterns and identify large-scale scams. Still, this is not as harmful as street-level lawlessness.

Things may change as the slump continues. Britain has not yet felt the full pain of cuts to welfare or government departments. People may grow more desperate. The police have made savings in areas such as human resources. In future the front line may suffer. The anger that fuelled riots in England in 2011 has not gone away, says Tim Newburn, a criminologist at the London School of Economics. But with so many reinforcing factors, the virtuous circle will be hard to break.