In December 2004, a private member's bill—the Succession to the Crown Bill—was introduced in the House of Lords. The government, headed by Tony Blair, blocked all attempts to revise the succession laws, claiming it would raise too many constitutional issues and it was unnecessary at the time. In the British general election the following year, Michael Howard promised to work towards having the prohibition removed if the Conservative Party gained a majority of seats in the House of Commons, but the election was won by Blair's Labour Party. Four years later, plans drawn up by Chris Bryant were revealed that would end the exclusion of Catholics from the throne and end the doctrine of agnatic (male-preference) primogeniture in favour of absolute primogeniture, which governs succession solely on birth order and not on sex. The issue was raised again in January 2009, when a private member's bill to amend the Act of Succession was introduced in parliament.