The Commons Public Administration Committee chairman Bernard Jenkin, said: "This underlines the all-too-obvious truth that investigations into ministerial misconduct are not an appropriate role for the Cabinet Secretary to undertake.
"Given time, attention and with his relevant experience, Sir Alex Allan (a former chairman of the Joint Intelligence Committee) might well have uncovered the truth."
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Nick Clegg will attempt to win over the female electorate when he kicks off the Liberal Democrats' general election campaign later today.
Up to £140 billion of savings could be released when over 55-year-olds are allowed to cash in their pension pots from April 6th.
The party's plans include a £2.5 billion Time to Care fund for the NHS, capping rail fare increases and 3,000 more midwives.