The Brown government has changed its mind on placing security scanners at every London tube station and mainline train stations across the country, because the technology does not work and the public would not tolerate the long delays such scanning would require.

Despite doubts from London Underground after the original trials Gordon Brown gave the scheme his support in November 2007. London Underground questioned the practicality of the technology as well as worrying that the queues created would provide a new target for terrorists.

But today Tom Harris, Under-Secretary of State for Transport, said the project would be abandoned because achieving airport-style screening is not feasible using today's technology, and the public would not stand for the delays caused and the invasion of privacy involved.

As we pointed out at the time the "security theatre" of such a scheme would be more important than any actual impact.

Instead of fixed scanners British Transport Police will continue to use some mobile scanners and sniffer dogs.

Along with metal detectors the government also trialled millimetre wave scanners at Paddington for the Heathrow Express. These scanners, which can look through clothes, proved particularly unpopular with young women. Those surveyed also doubted the technology could be used without causing significant delays.

The trial also tested finger and clothes swabbers and bag sniffers. ®