Following the "Orange Book", Cable was one of several Lib Dem MPs who oversaw the party's shift towards economic liberalism with the adoption of a more free market approach, a development which was suggested by some as having helped lead to the 2010 coalition with the Conservatives. In 2005, as Liberal Democrat Treasury spokesperson, he suggested the possibility of the party dropping its commitment to a 50p top rate of income tax, supported exempting people on low income from income tax completely, and explored the possibility of a flat tax, with the former two proposals later becoming party policy. Also in 2005, he said that there was no future for the Liberal Democrats to the left of New Labour. He was critical of what he considered the Labour government's slow response to cutting government waste, later accusing Labour of allowing a "writhing nest" of quangos to develop.