Despite staff guidelines designed to prevent conflicts of interest, freelance presenters have been allowed to work for dozens of large firms and Government departments. As well as making company videos, chairing business conferences and hosting meetings, the Independent has established that a number of presenters have trained senior executives in industry on how to handle interviews, a practice supposedly banned by the BBC.
All this activity takes place despite published guidelines which draw a completely different picture of BBC standards. The Producer Guidelines state that well-known BBC people - most of whom work for the corporation on a freelance basis for tax reasons - can expect to be asked to become involved in promotional work, corporate videos or "commercial events".
The guidelines say: "All such activity associates the individual with the product or service ... Any of these activities is unacceptable for BBC editorial people (including presenters and freelances) when they might compromise public trust in the integrity of our programmes or of those who make them."
The BBC is looking at ways to tighten up the guidelines because of the subjectivity of what "might compromise public trust". One senior executive said: "How do you prove that the public is worried about a presenter doing something in his or her spare time?"
Among the most sought-after names for hire is John Humphrys, one of the BBC's toughest and most respected journalists, an occasional presenter of the Six O'Clock News and anchorman for Radio 4's Today programme.
Inquiries have established that in recent years - completely within the limits of the private contracts the BBC allows its freelances to sign - he has worked for numerous companies and utilities including British Telecom, ICI, Nuclear Electric, the National Grid, National Westminster Bank, Marks & Spencer, Mercury Telecommunications, IBM, and the Department of Trade and Industry.
Promotions industry insiders say he has been paid up to pounds 5,000 for appearances. On one occasion, Mr Humphrys - who is thought to earn more than pounds 150,000 a year on a freelance basis for the BBC - appeared on a video privately produced by Nuclear Electric. The programme was later broadcast on the BBC's paid-for early morning Business Channel, Mr Humphrys presented it and Nuclear Electric paid him pounds 1,500, a company spokesman said.
Mr Humphrys has chaired an annual question and answer session between staff and management at British Telecom for the past three years. This year he hosted a two-day management conference for Mercuryand he has made several corporate videos, for internal company use only, for NatWest Bank and British Airways. In the NatWest video, he staged an interview with the bank's chief executive, Derek Wanless, a task he could conceivably have to perform for the BBC.
He denies that working for companies compromises hiswork as one of Britain's most rigorous interviewers, arguing that he works for so many no-one could accuse him of bias.
Other presenters who have undertaken corporate work include Nick Ross, Martyn Lewis, Andrew Harvey, James Naughtie, Anna Ford, Peter Hobday, Peter Sissons and Michael Buerk.
Several sources responsible for hiring celebrities say BBC journalists are regularly involved in coaching managers in industry on how to handle interviews. Companies are reluctant to admit having had their executives trained, but sources within ICI confirmed that Andrew Harvey and John Humphrys have conducted media training.
Mr Humphrys worked for ICI more than five years ago but Mr Harvey, through a company called Intermedia Training, still teaches the multinational's most senior executives how to handle interviews. Mr Harvey could not be contacted.
Of media training, the BBC's guidelines say: "There are real dangers when BBC people train individuals or organisations in how to perform on television and radio. No BBC presenter or editorial person regularly involved in news and current affairs or topical programmes should coach people in how to be interviewed.
"We must not be party to the training of potential interviewees in how to present themselves in the best light."
One senior broadcaster said yesterday he had never heard of the producers' guidelines. "If the BBC expect us to stick to them, they really ought to have told us about them," he said.
If John Birt, Director-General of the BBC, carries out his threat to clamp down on outside work, he could face a revolt. Another well-known newsreader said: "Newsreaders at ITN have always been paid more than us, so doing outside work was seen as a perk. If they tried to stop us doing it, I think they would find that they would lose a lot of their top people.
"I would just say, 'fine, I'll go completely freelance. If you want me to present this programme or that programme, then give me a call. If you're lucky, I might be available'."Reuse content