"In September 2006 the city of Irving, close to Dallas, decided that it wanted to help fight illegal immigration. So it signed up for the Criminal Alien Programme (CAP). The programme, run by the Immigration and Customs agency, asks local law officials to give them a call if they suspect someone they have arrested may be an illegal immigrant.

Irving is not the only city to have joined, but it is probably the most enthusiastic. Since CAP's inception, some 1,700 people from Irving, a city of officially about 200,000 souls, have been handed over for deportation. Opposition to CAP has suffered some public-relations setbacks. In November an activist, Carlos Quintanilla, was arrested after a policeman spotted him giving a television interview on East Irving Boulevard. He had seven outstanding warrants. But such moments aside, the programme's opponents are right to be concerned about it. They argue that it encourages racial profiling, is too punitive and harms families. No reliable measure exists of how many people have left the city out of fear or frustration, but the local school district says it has lost hundreds of students this year.

Objecting from the other side are people who say that Irving policemen should not be asked to shoulder a federal task. In November the federal government asked north Texas officials to stop detaining people over traffic violations and certain misdemeanours, such as bouncing a cheque. There were too many referrals, they said, and not enough resources to look at them all.

So the programme has its problems. And Irving is just one of several places in the Dallas-Fort Worth area to struggle with its response to illegal immigration. City commissioners in Collin County recently announced that non-profit clinics will not receive county money if they treat illegal immigrants. In May the suburb of Farmers Branch approved an ordinance that would require landlords to verify the legal status of prospective tenants. Landlords are contesting the ban, saying that it puts an undue burden on them, and lawsuits have prevented it from taking effect.

Understandably, people who are frustrated by federal inaction on immigration may turn to local initiatives. But no one benefits when these are poorly conceived and arbitrarily applied." (The Economist, December 15, 2007)