But ICM poll suggests Lib Dem voters would like a referendum on both

While the Lib Dems' MORI poll shows that, offered the choice, people prefer a referendum on EU membership to one just the Treaty, Iwantareferendum have in turn released an ICM poll of people who voted Lib Dem at the last election suggesting they'd prefer to be asked about both.

In ICM's poll support for a referendum on the treaty amongst Lib Dems stands at 67%, with 33% opposed. The MORI survey found support for a referendum on EU membership was at 49% amongst Lib Dem voters, though the questions were asked in a very different way so a straight comparison is somewhat unfair.

ICM's poll suggests only 25% of Lib Dem voters supported the idea that there should be only a one question referendum on EU membership, but 70% would prefer a two-question referendum that asked about both EU membership and the Lisbon treaty.

This appears to be a direct contradiction to the Lib Dem commissioned MORI poll, which amongst Lib Dem voters found 30% wanted a referendum on the treaty, 37% wanted a referendum on membership and 7% wanted both. The reason is the different questions asked, or more specifically, the different prompts people were given.

In ICM's question Lib Dem voters were asked to chose between a one question referendum on just membership or a two-question referendum on both membership and the treaty. In MORI's question people were prompted with the options of a referendum on the treaty OR a referendum on membership. While some people said both and MORI dutifully recorded it, it wasn't actually given as an option, so many people would have assumed that had to give one of the options presented to them and that both was not up for grabs.

It would appear therefore that, while in forced choice between referendums on just the treaty or just EU membership Lib Dem voters would go for the latter, if presented with the chance to have both they'd opt for that.

Of course, this is largely a debate about the number of angels dancing on the head of a pin. Why pay so much attention to exactly what type of referendum Liberal Democrat voters would like? Especially since, as I've said in the past, questions on referendums nearly always show majority support - "Do you want a vote on this issue, or are you a nitwit who shouldn't be allowed a say?". The only real impact is if it has an affect on Lib Dem support. On that question ICM asked Lib Dem voters (or at least, 2005 Lib Dem voters...remember some of these people will already be backing other parties) how they would react if the Liberal Democrats voted against a referendum. 32% said it would make them less likely to vote for the Liberal Democrats next time round (including 10% would said they would definitely not vote Lib Dem), 7% said it would make them more likely to vote Lib Dem.

I am always highly sceptical about questions like this - we don't know how many of those would not votes are people who wouldn't vote Lib Dem anyway. Given this is a sample of former Lib Dem voters there shouldn't be that many such people. The second issue is that people may be susing the question just to register their dislike of the policy and, when push comes to shove, will still vote for their party. Even with those caveats in mind, it does suggest some disquiet amongst Lib Dem supporters. The probability though is that, in reality, Europe isn't the main thing driving the voting intention of most Lib Dem supporters - something underlined by the last question.

ICM also asked Lib Dem voters what their general attitude towards Europe was. 11% wanted more European integration, 33% supported the status quo, 46% thought Europe should have less power and 10% supported leaving the EU altogether. Obviously it would be more useful if we had the answers from supporters of other parties to put these answers in context, but the balance of opinion seems to be towarsd Euroscepticism, and it does appear that many Lib Dem supporters back the party despite having very different views on Europe.