Music mogul Simon Cowell has been named on the secret client list of one of the four rogue private detectives who were jailed last year.
Blue-chip companies including Credit Suisse, Allianz, and Deloitte, and a number of high-street solicitors are among the 102 names on the list drawn up by the Serious and Organised Crime Agency (Soca) after an investigation into the activities of the private detectives, says the Times.
The Commons Home Affairs Select Committee has demanded that Soca publish the list, arguing that it is unjust that journalists have been pursued by police and some prosecuted for using private detectives to gain information illegally, while companies and individuals on the list have not been exposed. Chairman Keith Vaz MP says the committee will publish the list on Monday if Soca does not.
However, law enforcement officials argue that making all of the names public could endanger ongoing investigations, and has enlisted the support of Britain's most senior anti-terrorism officer, the Information Commissioner and Cabinet Minister Andrew Lansley to insist that plans to publish are postponed.
Information Commissioner Sir Christopher Graham, Sir Alan Beith and James Arbuthnot, the chairmen of Westminster's Justice and Defence Select Committees, respectively, also wrote to Vaz to voice objections to plans to reveal the names.
"'This is very suspicious. It seems there is some sort of co-ordinated operation going on to prevent us from publishing what could be very embarrassing information," one committee MP told the Daily Mail.
Tory Michael Ellis said: "There don't seem to me to be any issues of national security or other issues pertaining to the wider national interest."
Soca has stressed that the presence of a person's name on the list does not imply that the individual hired the detectives to procure information or that they knew that the private detectives used illegal means to gain information.
Speculating why a firm may have hired the detectives, one blue-chip client told the Times: "We think this may be the result of employing security firms to do background checks on some new recruits and they possibly subcontracted the work to others."
Last year, four private detectives were jailed for between four and six weeks for "blagging", or obtaining private information, including people's medical records or credit card records, by deception.