In 2000 the Stewart Report was commissioned, investigating the risks of mobile phone usage. Whilst it did not come to any firm conclusions, it did suggest that the levels of radio frequency radiation emitted by mobile phones and masts had the potential to have an adverse affect on human health.
OFCOM, the industry regulator for telecommunications, took this report fairly seriously. In particular they took account of one of the key recommendations of the Stewart Report, that the government set up a database of all mobile phone base-stations and masts. This resulted in a voluntary scheme, where mobile phone operators provided information to OFCOM which was compiled into a search interface called Sitefinder. Go on, click on it, it's really user friendly, and you can check if a mast is near you right now. OFCOM manage this service, but do not provide the underlying data to users.
On 11 January 2005, a Freedom of Information Act 2000 request was made to OFCOM for the underlying data in the sitefinder database in specified file formats. OFCOM replied on 27 January 2005, declining the request and citing the Environmental Information Regulations 2004 6(1)(b) (which apply here in harmony with the Freedom of Information Act), since the information is 'already publicly available and easily accessible in another form or format'. Following some further wrangling, they also refused to disclose the information because of the Environmental Information Regulations 2004 12(5)(a) and (c), namely that they could refuse to disclose the information to the extent it would adversely affect 'international relations, defence, national security or public safety' (on the basis that it would reveal the locations of police/emergency services communications equipment) or due to 'intellectual property rights' (because the data belongs to the mobile phone operators).
The applicant did not accept this, and wrote to the Information Commissioner to ask them to review OFCOM's decision. In a detailed decision, the Information Commissioner upheld the applicant's request and dismissed OFCOM's arguments, ordering the data to be disclosed. This decision was subsequently endorsed by the Information Tribunal who upheld the Information Commissioner's judgment (albeit with some difference in reasoning).
OFCOM has reportedly decided to appeal this decision to the high court.
I must confess I'm with OFCOM on this one, despite being very much in favour of the transparency and availability of information. Some of their arguments seem relatively tenuous (prevention of terrorism being the most interesting) but their position is fairly strong overall.
As things currently stand, the public have a user friendly means to access information which belongs to the mobile phone operators. They can check if a mobile phone mast is near them, and act accordingly. The only reason I can think why anyone would want a complete dataset would be either to make some commercial gain (e.g. spotting gaps in the mobile phone network) or to use against mobile phone companies. Without parliamentary intervention, mobile phone companies shouldn't be required to provide information which can only harm their interests. Like or loathe your mobile phone company, that's just not fair.
