WHEN both the executive editor of the blog ConservativeHome and the General Secretary of the Trades Union Congress are militating against a Bill, its prospects begin to look uncertain.

Nevertheless, the Transparency of Lobbying, non-Party Campaigning and Trade Union Administration Bill passed its second reading in the House of Commons on Tuesday, by 309 votes to 247.

Published by the Government in July, the day before the summer recess, the Bill reduces the amount of money that a third party (as distinct from a political party) can spend on campaigning in the year before an election from £988,500 to £390,000. It also broadens the definition of campaigning activities to include staff time, media appearances, leaflets, and blogs. Spend- ing per constituency is limited to £9750.

The Government argues that this will "avoid the situation we see in other countries, where unregulated spending by vested interests means that it might not always be the best candidate who wins an election, but the one with the richest supporters".

The chief executives of Oxfam, Christian Aid, and Tearfund are among the 47 signatories to a letter from the National Council for Voluntary Organisations to the Government which warns that the rules "risk seriously hampering their ability to speak up on issues of concern" (Leader, 30 August).

It explains that "entirely party-politically neutral" campaigns could be defined as partisan, and thus would be limited by the rules. Charities would also be discouraged from working together for fear of breaching the spending limits, it suggests.

Last month, the General Secretary of the TUC, Frances O'Grady, described the Bill as "a crude and politically partisan attack on trade unions, particularly those that affiliate to the Labour Party". It would "severely limit any organisation's ability to criticise government policies in the run-up to an election".

In 2010, third parties spent a total of £2.8 million on campaigning, about nine per cent of that spent by political parties. None of the third parties spent more than 70 per cent of the current limit (£988,500).

In a briefing for the debate in the House of Commons on Tuesday, the Electoral Commission warned that the Bill "creates significant regulatory uncertainty for large and small organisations that campaign on, or even discuss, public-policy issues in the year before the . . . General Election, and imposes significant new burdens on such organisations".

During the debate, the Shadow Leader of the House, Angela Eagle, described the Bill as "hurried, badly drafted, and an agglomeration of the inadequate, the sinister, and the partisan".

The Deputy Leader of the House of Commons, Tom Brake, insisted that charities would still be able to support specific policies advocated by political parties without having their expenditure limited, provided that they were "maintaining their political neutrality and independence".

The Bill also introduces a statutory register of lobbyists, who will have to disclose the names of their clients, and strengthens existing requirements for trade unions to keep accurate records of their membership.