MPs have rejected a call from Labour demanding that ministers publish a confidential Whitehall document outlining the potential risks of government proposals to reshape the NHS in England.
Members voted by 246 to 299, a majority of 53, to reject the motion which called for the immediate release of the so-called "risk register".
The opposition day debate on 22 February 2012 came after 93 MPs, including 15 Liberal Democrats, signed an
early day motion
(EDM) calling on the government to release the document.
The information commissioner has ruled that the register should be published, but the government is challenging the ruling, with the appeal due to be heard in early March.
Andrew George, one of the Liberal Democrat MPs who signed the EDM, told the Commons the register's publication was "unlikely to change a single mind on the issue".
But, he said, people should have "as much information available as possible" when considering "the biggest ever reorganisation of the NHS".
Labour's Valerie Vaz agreed the register should be published, telling the chamber: "The people want it, and they should have it."
Meanwhile, Conservative Mark Simmonds dismissed the opposition day debate as a "red herring", claiming it distracted from the "necessity for reform" in the health service.
Fellow Conservative Gareth Johnson supported the government's decision, saying the register's confidentiality allowed civil servants to "think the unthinkable" without the fear their views would later be released to the public.
But Labour's former health secretary Frank Dobson disagreed, telling MPs the government was "foolish" for not publishing the document because it made the public assume "they must have something to hide".
Liberal Democrat John Pugh worried that the Health and Social Care Bill, the legislation that enacts the changes to the NHS, was "toxifying the Tories" and was "sadly detrimental" to the Liberal Democrats.
Summing up, shadow health minister Liz Kendall quoted a newspaper interview with Information Commissioner Christopher Graham, where he said the register should be published before the legislation is passed by Parliament.
The bill is currently being considered by the House of Lords, but crossbencher Lord Owen is expected to table an amendment which would delay its passage until the appeal is heard on 5 and 6 March.
Ms Kendall urged Liberal Democrat MPs to support Labour in the voting lobby, to "show they really support the EDM that they've signed".
Responding for the government, Health Minister Simon Burns reiterated the argument that releasing the register would compromise the frank discussions ministers and officials have behind closed doors.
He repeated Health Secretary Andrew Lansley's view that experts would be less candid in their comments if they knew their views would later be released publically.
"If they [risk registers] are to remain useful, they need to remain confidential," he told MPs.
Later analysis of the vote showed that just four of the 15 Liberal Democrats who signed the similarly-worded EDM rebelled against the government.
They were: Andrew George (St Ives), Mike Hancock (Portsmouth South), Greg Mulholland (Leeds North West) and John Pugh (Southport).
Duncan Hames, a Lib Dem ministerial aide who signed the EDM, voted against the Labour motion.
You can watch the first part of the debate