The Police have started video recording interviews with suspects and witnesses and the clips are likely to start being shown during courtroom trials very soon.

The move is part of sweeping reforms under the Police and Criminal Evidence Act (PACE.) It means that the old-fashioned method of recording interviews on audio cassette has been replaced with video recordings. The new method has been used since June. PACE implementation manager Mark Crampton has previously commented that this is backed by prosecutors and defence lawyers alike for the positive effect it will have on trials.

"There are a number of obvious advantages, because at the moment all we have is a verbal account we can't see the expressions on someone's face and how they react to a question," he said.

"It will also make it clear who makes a comment, because sometimes if there's a lot of people in the interview it's not always clear."

Giving an update on the technology this week, he said: "Nearly all of our interviews are being video recorded and the courts are making arrangements to get playback facilities in the form of plasma TV screens in courts by the end of the month."

The Police videos have a clock counting each second, and are tamper-proof so they can't be edited. It is anticipated that the new technology will eventually be used to allow vulnerable witnesses such as rape victims and young children to give "live" evidence in court by video link too.

The Police and Criminal Evidence Act, which was passed by Parliament in 2005, has already seen old-style identification parades replaced by new video parades employing computer images.

High-tech fingerprinting machines have also been brought in to replace the old "ink and roller" method. These allow the better quality prints to be stored as digital files.