The long running inquiry into party funding by the Con Dem appointed Committee on Standards in Public Life is recommending that the clock be turned back 84 years and trade unionists be required to opt in rather than opt out of union political funds. Last time around this resulted in a halving of political funds:http://www.guardian.co.uk/politics/2011/nov/22/party-funding-shakeup-rejection-promises
'In 1927, in the immediate aftermath of the defeat of the General Strike, the Conservative government under Stanley Baldwin turned the requirement around to individual members having to actively opt in to paying the political levy, and apathy cut the combined union political fund by around 50%. In response, one of the first acts of the Labour government of 1945 was to restore opting out.'
http://www.historyandpolicy.org/papers/policy-paper-05.html