Information Commissioner Christopher Graham has locked horns with the Government over its decision to veto publication of a report detailing the risks associated with controversial reforms of the NHS.
Health Secretary Andrew Lansley deployed his veto to block an Information Tribunal ruling that he should meet Labour demands to disclose the document.
The November 2010 Transition Risk Register set out internal Government assessments of the risks posed by the reforms in the Health and Social Care Act, which became law in March.
Labour MP John Healey, who was shadow health secretary when it was drawn up, called for the register to be published under the Freedom of Information Act.
A Government appeal was then rejected unanimously by the Information Tribunal.
Graham said there was 'no evidence'to support the claim made by ministers and senior civil servants that publication would have a "chilling effect" on officials' willingness to be frank.
But the Cabinet agreed last week that the ministerial veto should be used.
In his report to Parliament, Graham said the decision did not comply with the "statement of policy" regarding the use of the veto.
The only three previous uses of the veto all involved Cabinet material, he noted.
"The commissioner would wish to record his concern that the exercise of the veto in this case extends its use into other areas of the policy process.
"It represents a departure from the position adopted in the Statement of Policy and therefore marks a significant step in the Government's approach to freedom of information."
Healey has said he considering seeking judicial review on the decision.
'In blunt terms, this report tells Parliament that ministers have ridden roughshod over existing FoI law and it warns that this case signals plans to change the law and roll back the public's right to know.
"The political veto has only ever been used before to protect Cabinet material. This move widens the span of Government information protected under veto. It is a landmark in the executive's bid to draw a wider veil of secrecy over Government decisions.
"I have challenged the Cabinet's veto in the Commons, and I've have not ruled out a challenge in the courts."
Shadow health secretary Andy Burnham said: "This unequivocal report is severely embarrassing for Andrew Lansley and a Cabinet that promised to be open and transparent.
"It finds Mr Lansley's desperate efforts to keep the risks of his NHS reorganisation secret are not justified and it backs Labour's consistent call that patients, public and Parliament have a right to know.
"But though the Government won't publish, people are beginning to see the risks to the NHS becoming a reality on the ground, with patients left on trolleys in corridors and thousands of nursing posts being lost. People will conclude that the Health Secretary was warned about these dangers by his own civil servants, ploughed on regardless and is now frantically trying to cover it up."