The Government narrowly won the key Commons vote tonight to extend pre-charge detention of terror suspects to 42 days... amid claims that nine Democratic Unionist MPs who saved Gordon Brown had been 'bought'.
After weeks of arm twisting and a series of concessions, the power for ministers to exercise the controversial "reserve" power was backed by 315 to 306 - a majority of just nine.
A total of 36 Labour MPs defied the party whips to vote with the opposition against the measure (see list below).
The Prime Minister was effectively saved by the votes of the nine Democratic Unionist MPs who agreed at the last minute to march into the division lobbies with the Government. Tory opponents demanded to know if anything had been promised to the DUP.
"We won the argument. They bought the votes," the Shadow Home Secretary David Davis told Sky News. "It wasn't the argument that won the day, it was the whips' operation. Gordon Brown can't be proud."
When the key result was announced Tory and Liberal Democrat backbenchers pointed angrily at the DUP benches in the chamber, with one Member shouting: "You were bought!" before Mr Martin intervened to restore order.
The Democratic Unionists rejected accusations from opponents of the anti-terror measure that they had been bribed by ministers.
Gregory Campbell, one of the DUP MPs, said: "It was a very close call because of the complicated nature of safeguarding the UK as a whole from the international terrorist threat and preserving the civil liberties of the accused. But we came down in favour of the 42 days on the merits of the case."
He added: "The good thing for us is that it proves that now beyond doubt that the DUP MPs are crucial and we will be reminding them of that on each and every occasion that that comes into play, which will probably be more and more often now."
The 36 Labour rebels were:
Diane Abbott (Hackney North & Stoke Newington), Richard Burden (Birmingham Northfield), Katy Clark (Ayrshire North & Arran), Harry Cohen (Leyton & Wanstead), Frank Cook (Stockton North), Jeremy Corbyn (Islington North), Jim Cousins (Newcastle upon Tyne Central), Andrew Dismore (Hendon), Frank Dobson (Holborn & St Pancras), David Drew (Stroud), Paul Farrelly (Newcastle-under-Lyme), Mark Fisher (Stoke-on-Trent Central), Paul Flynn (Newport West), Neil Gerrard (Walthamstow), Dr Ian Gibson (Norwich North), Roger Godsiff (Birmingham Sparkbrook & Small Heath), John Grogan (Selby), Dai Havard (Merthyr Tydfil & Rhymney), Kate Hoey (Vauxhall), Kelvin Hopkins (Luton North), Glenda Jackson (Hampstead & Highgate), Dr Lynne Jones (Birmingham Selly Oak), Peter Kilfoyle (Liverpool Walton), John McDonnell (Hayes & Harlington), Andrew Mackinlay (Thurrock), Bob Marshall-Andrews (Medway), Michael Meacher (Oldham West & Royton), Julie Morgan (Cardiff North), Chris Mullin (Sunderland South), Dr Doug Naysmith (Bristol North West), Gordon Prentice (Pendle), Linda Riordan (Halifax), Alan Simpson (Nottingham South), Emily Thornberry (Islington South & Finsbury), David Winnick (Walsall North), Mike Wood (Batley & Spen)
The Government won a second vote - by 315 votes to 294, majority 21 - to include all the new safeguards in the Bill but now faces an uphill struggle to get the measure through the Lords.
Downing Street had earlier forecast that the outcome of the vote was looking "very, very tight".
Facing one of the biggest tests of his leadership, the Prime Minister had been calling Labour MPs personally to make the case for the extension.
In a sign of how tight the situation was, Foreign Secretary David Miliband had to cut short a visit to Israel to attend the crucial divisions in Westminster.
The row over detention dominated the day at Westminster.
At question time, Tory leader David Cameron accused the Prime Minister of "ineffective authoritarianism" by proposing to detain terror suspects for 42 days without charge.
Urging MPs to follow their consciences, Mr Cameron branded the Government's plans "unworkable" and a "symbolic assault on liberty," which would "trash" the nation's hard-won civil liberties.
But Mr Brown insisted the change was needed to tackle increasingly sophisticated terrorism and accused the Tories of "opposition for opposition's sake".
He said he would rather act in "calmness" now than try to bring in "panic" measures at a time of emergency later.
Citing police backing, he insisted it was his duty to do not what was popular but what was right and necessary for the security of the UK.
Liberal Democrat leader Nick Clegg accused the Prime Minister of "playing politics with our civil liberties", and insisted the measures would be blocked by the Lords even if the Government wins backing from MPs.
When the key debate got under way in the crowded chamber, Home Secretary Jacqui Smith confirmed a fresh concession that suspects released without charge after being held under the scheme will be eligible for compensation.
Ms Smith said terrorist threat was "real and serious" and "more ruthless than any we have faced before" - raising the prospect of a radioactive 'dirty' bomb being used in a future plot.
"We are not proposing a permanent, automatic or immediate extension to pre-charge detention beyond 28 days," she said.
"Instead the Bill contains a reserve power that can only be used in exceptional circumstances, only with the support of the Director of Public Prosecutions, only with the backing of Parliament in a vote in both Houses, only with strong judicial safeguards and only for a temporary period before automatically lapsing."
Liberal Democrat spokesman Chris Huhne attacked the "feeble" safeguards in the Bill while Labour's Andrew Dismore, chair of the joint committee on human rights, warned that far from being a "deterrent to terrorism", the Bill could actually "make things worse".
He said the Government had "not made the case" for change, adding: "This is not a deterrent to terrorism, it's an investigation tool.
"It could make things worse if the consequences are alienation, less cooperation, less information, less intelligence."
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