Six months later, a judge trying a Customs and Excise drugs case decided to hear evidence from a witness in Pennsylvania via the studio's facilities. This proved a more nerve-wracking experience for Julian Bradley, studio manager, as problems with the American system and relevant software initially held up proceedings.
"I had a roomful of lawyers, a bunch of FBI men in blazers and grey trousers and I was popping in and out of the room saying: 'Eighth time lucky, your honour'," Mr Bradley recalled, wincing at the "horror" of the system going wrong. However, he sorted the problem out with only a slight delay and the hearing proceeded smoothly.
Use of the Bar Council's pounds 70,000 video-conferencing facilities has increased twofold in the six months to January this year over the same period to January 1995. Last month alone, it was used for 56 hours, compared with five hours in January 1995 and 11 in 1994.
However, Mr Bradley, who combines his job with the administration of the Criminal Bar Association, said: "There is still a resistance to using video conferencing among the legal profession, whether through fear of technology or the fear that somehow they are going to lose something by not having a witness present.
"We are marketing the studio through mailshots, advertising and word of mouth because there is a tremendous potential for growth. While video conferencing is still an embryonic market, it is becoming more competitive as more studios are being set up.
"The benefits of using a video link are easy to sell - savings in costs, time and effort," Mr Bradley explained. "For example, a video conference with witnesses in New York will cost pounds 500 an hour maximum. A business- class return flight for just one witness is pounds 2,504, let alone the costs of hotels, expenses, time away from work."
It costs pounds 50 for a member of the Bar to hire the studio for half an hour, pounds 75 for commercial users. There is an extra charge of pounds 40 per half-hour for taking advantage of its 24-hour service, "but believe me, at 3am I deserve it", Mr Bradley joked.
The Bar Council facility, now five years old, has only recently moved to Chancery Lane, where it has a room large enough to accommodate a court or conference of 30 people. It costs about pounds 45,000 a year to run.
The system operates via digital telephone lines and can link up with most countries. Some barristers' chambers in major UK cities have their own systems and regularly link up with the Bar Council studio for conferences with expert witnesses or counsel.
Sitting in Chancery Lane, the people at the other end appear almost life size on the 32in screen, with the camera able to zoom in for close ups or pan around the room. Documents can also be scanned on to the screen.
The picture quality is very good, although movements appear jerky and blurred. A slight time delay in the sound initially feels unnatural but soon acts like a chairman as those involved wait until they are sure the other person has finished speaking.
From Mr Bradley's experience, the feeling of being on Candid Camera does not last long. "It takes the average user about 10 minutes to build up a rapport with the person at the other end."
In 1994, commercial organisations booked about 75 per cent of the 247 hours the studio was used, generally for job interviews or multi-national meetings, and only 25 per cent was taken by the Bar. A year later the split was 50/50.
So far, 80 per cent of the Bar work involves civil cases. Pre-trial interviews and conferences with expert witnesses via links with lawyers in most UK cities provide its "bread and butter" work.
The opportunity to hear evidence from witnesses via live television links in criminal trials is limited under Section 32 of the Criminal Justice Act 1988 to cases involving murder or manslaughter, Serious Fraud Office prosecutions or if the witness is a child under 14.
However, in the blackmail case, the judge decided that although it fell outside the statutory provisions he was prepared to allow the witness to be heard via the video link because the defence was anxious to hear his evidence live.
In the Customs and Excise drugs case, the judge ruled that the evidence was admissible under Section 23 of the Act, which allows witnesses to make a documentary statement when they are outside the UK and it is not reasonably practicable for them to give evidence in person.
John Horne, executive secretary of the Bar Services and IT Committee, said an inquiry last year by Judge Lyons recommended that the restrictions on the use of video links in criminal trials should be eased. "We would like to see them abolished. It would not be a free-for-all because it would be up to the judge, having considered the views of all parties, to decide whether it was an appropriate way of taking evidence from a witness," Mr Horne said.
Enthusiasts of video conferencing include members of 8 King Street chambers in Manchester. Peter Whitman, senior clerk, said they first tried out the system about 15 months ago when they took part in a video-link IT workshop as part of the 1994 Bar Conference.
The chambers, which has 28 members including three QCs, specialises in medical negligence cases and found the facilities so useful for conferences with experts around the country and overseas that they bought their own system for about pounds 20,000.
Martin Hulbert, fee control clerk at 5 Fountain Court chambers in Birmingham, said they bought their own system about three years ago for pounds 40,000, largely for civil cases. He said there were problems using the system for criminal cases, particularly with prisoners who were concerned about confidentiality.
"There is a lot of worry that it is going to be impersonal. But within 10 minutes, you forget there is a TV screen and chat as though the person was in the room," he said.
General Council of the Bar video-conferencing studio, Chancery House, 353-364 Chancery Lane, London WC2A IQX (0171-242 1289).