One of the Prime Minister’s closest aides advised him not to raise taxes for the lowest-paid workers in the country, more than a year before the decision became a political crisis.
Spencer Livermore was until recently the head of political strategy at 10 Downing St.
In December he was named the most influential gay man in British politics by PinkNews.co.uk.
His departure from the Prime Minister’s staff in March was seen as a serious blow to Mr Brown. He had been a trusted adviser since the first days of the government.
While chief political and strategy adviser to then-Chancellor Brown he advised against the abolition of the 10p rate of tax, announced in the 2007 Budget.
The Times reports Mr Livermore, “feared a public reaction against the change because it increased taxes on some on low pay.”
That advice has proved accurate.
The government has been forced into a humiliating and expensive climbdown over the abolition of the 10p tax rate.
Earlier this week Chancellor Alastair Darling announced that £2.7 billion would be set aside to raise the threshold at which people on lower incomes start to pay tax by £600.
The threat of a revolt among Labour MPs horrified that more than five million of the lowest-earning taxpayers would be worse off under the new tax regime spurred the Prime Minister into action.
The 10p tax row has been hugely damaging for the government and led to questions about Mr Brown’s suitability for Number 10.
Known as an ultra-loyalist, Mr Livermore refused to comment on The Times story.
“Advice given in private should stay in private,” he told the paper.
Livermore moved from Downing St in March to become Senior Strategist at Saatchi Saatchi and Fallon, a leading consultancy and advertising company.
He remains close to Gordon Brown and is expected to play a key role in the next election campaign.
Livermore became active in the Labour party in 1994, and by the 1997 election, less than a year after graduating from LSE, he was working for the party’s Economic Secretariat.
In 1998 he became a Special Adviser at the Treasury and his close relationship with the Prime Minister began.
Brown, the arch-strategist, asked his young apprentice to take up the post of Head of Research for the 2001 election campaign, when Labour held on to all but a handful of seats.
He was then appointed Special Adviser to the Chancellor of the Exchequer. By 2005, he was on Gordon Brown closest advisers.