The F.B.I. has a long history of abusing its authority to spy on domestic groups, including civil rights and anti-war activists, and there is a real danger that the new rules would revive those dark days. Clearly, the Bush administration cannot be trusted to get the balance between law enforcement and civil liberties right.

Civil liberties and business travel groups have pressed the Government to disclose its procedures as an increasing number of international travellers have reported that laptops, mobile phones or other digital devices have been taken and examined.