Seems that charges of fraud has been a standard weapon against him all his career:
Early and personal life
Galloway was born in Dundee, Scotland. He went to the Harris Academy, and on leaving school worked for a garden centre and then for Michelin tyres. In 1977 he was appointed as a Labour Party organiser, and became well known in Scottish Labour politics for his firebrand speeches. He was elected to the Scottish Executive - the senior body within the Labour Party in Scotland - and in 1980 became Chairman of the Scottish Labour Party at the age of 26, one of the youngest in history.
In 1983 Galloway became General Secretary of the charity War On Want, which had strong Labour Party connections (it had been founded by Harold Wilson). He increased its income sevenfold in three years, but faced accusations of misuse of his expenses account, which was £21,000 in 1985-86, to stay in luxury hotels when on foreign trips. He paid back £1,720 after an audit identified a lack of controls, but was cleared of any dishonesty. War On Want was found to have been insolvent, and subsequently dismissed all its staff and went into administration. It was rescued and relaunched in 1991.
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Parliamentary career
Member of Parliament, Glasgow
Galloway was selected as Labour candidate for the Glasgow Hillhead seat formerly held by Roy Jenkins of the SDP. He ran for the Labour Party National Executive Committee in 1986 but came next to last; at the 1986 Labour Party Conference he made a strong attack on Shadow Chancellor Roy Hattersley for not favouring exchange controls.
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In 1990, a mysterious advertisement appeared in the Labour movement magazine Tribune headed "Lost: MP who answers to the name of George", "balding and has been nicknamed gorgeous", claiming that the lost MP had been seen in Romania but had not been to a constituency meeting for a year. A telephone number was given which turned out to be for the Groucho Club in London, from which Galloway had been blackballed. Galloway threatened legal action and pointed out he had been to five constituency meetings.
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http://en.wikipedia.org/wiki/George_GallowayBasically, if you're as far left as George, you can expect the conservative press to dog you with charges 24x7. Keeps you occupied...