[JURIST] Both houses of the UK parliament should approve any UK government proposal to opt-in or opt-out of certain policy provisions of the EU reform treaty [JURIST news archive], formally known as the Treaty of Lisbon [official website; PDF text], the UK House of Lords Constitution Committee [official website] concluded Friday in a 124-page report [PDF text] on the implications of the treaty for the largely-unwritten UK constitution. The committee found that the treaty would not affect UK sovereignty, but said it was important for parliament to have the ultimate say on whether the UK should adopt optional provisions in areas such as security and justice. The committee's recommendation comes one week before debate on the European Union (Amendment) Bill [PDF text; materials], which would incorporate the Treaty of Lisbon into UK law. The Guardian has more.

Earlier this month, the UK House of Commons passed [JURIST report] the bill 346-206. The version passed did not mandate parliamentary approval of opt-in and opt-out provisions. The Commons previously rejected holding a national referendum [JURIST report] on treaty ratification, though supporters of that proposal are still hoping that the House of Lords will back a popular vote on the treaty, rather than allowing parliamentary ratification. The treaty must be ratified by all 27 EU member states before it can take effect, though each country may choose the method of ratification. Six countries have ratified the reform treaty; so far, Ireland is the only EU member state that has chosen to hold a referendum on the issue.