Damian McBride compared his activities as Gordon Brown's spin doctor to those of a "rogue trader in the 1980s", saying Labour leaders were unaware of the way he operated.
McBride told ITV's Daybreak: "I'd compare it to when we had some of the rogue bankers ... people weren't asking enough questions about how they were making their profits."
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An independent investigation has begun into finances at taxpayer-funded Broadmoor Hospital.
While the economy has shown signs of improving, the number of UK companies issuing profit warnings has hit a six-year high, research shows.
The Child Support Agency has collected £1.2 billion in maintenance over the past year, with £330 million coming direct from pay packets.