It has now been revealed that batches of "the torturer's friend" were sent to such countries as Saudi Arabia, Egypt and Botswana, and the Department of Trade and Industry (DTI) has admitted that the wrong figures were given in replies to parliamentary questions.
The batons are considered an essential tool for the modern torturer. Capable of delivering between 40,000 and 150,000 volts, they cause convulsions, vomiting, paralysis, and in extreme cases death.
They are illegal in the UK but have been supplied by British companies on a number of occasions.
The Independent recently revealed that batons supplied from Britain to China had been used in torturing political prisoners.
In a series of answers to MPs, the DTI had said that it had issued only one licence to export the shock batons and that that was in 1993.
After doubts were expressed about the accuracy of the figure, ministers in the new Labour administration instructed officials to double check the number of licences issued.
The department has now had to admit that it misled MPs.
In a letter to the Labour MP Ann Clwyd, the DTI said that answers given to her were wrong. Officials say they have discovered that at least a further three licences were issued during the period.
These allowed shock batons to be sent to Saudi Arabia, Botswana and Egypt. The department blames "problems with the computer databases of the DTI's Export Control Organisation".
Ms Clwyd commented: "I don't think apologising in a letter is good enough. I was pushing hard on this issue. The previous government told me an untruth. I think the then minister, Ian Taylor, should apologise on the floor of the House.
"How can we be sure that these new figures are accurate? I am still unhappy about the whole question of the supply of electronic shock batons. I still don't think we have got to the bottom of it."
The original parliamentary questions from Ms Clwyd and other MPs arose out of a 1995 Channel 4 Dispatches programme, "The Torture Trade". The programme investigated British companies that were supplying paramilitary equipment which was used for torturing suspects in Third World countries.
Undercover reporters posing as potential Middle Eastern buyers caught businessmen offering to sell the electronic batons illegally.
The then newly privatised Royal Ordnance offered to sell electronic shock shields and batons worth $3.4m (pounds 2.06m). In a secretly filmed meeting, a salesman, Phillip Morris, boasted that the Royal Ordnance had supplied 8,000 batons to Saudi Arabia in 1990 as part of the massive Al-Yamamah arms deal.
"When I did the Saudi thing the rough price on, I think, the 26in baton was round about pounds 70," he said, adding: "I've said too much in telling you we sold them to Saudis in any numbers."
When the programme was broadcast, both Royal Ordnance and the Government denied that any batons had been supplied.
Shock batons had turned up in the hands of the Saudi police in the early 1990s. According to Amnesty International, they are being used to torture prisoners in Saudi jails.
In 1995 the DTI assured Ms Clwyd that no licences were issued to export batons to Saudi Arabia.
It now admits that in August 1993 the DTI received a request for a licence to supply one baton and "other goods" free of charge to the Saudi Ministry of Interior. The licence was issued on 8 September 1993.
Ms Clywd put down a series of further questions in the House of Commons on Friday about the supply of the shock batons. They include questions about how many batons the British have supplied to Saudi Arabia.Reuse content