Labour's current plan to embarrass the Lib Dems over its clothes-stealing mansion tax policy is an Opposition Day debate in the Commons. But, in a mark of how serious the party is to score a political point on this matter, I understand that it is also considering tabling an amendment involving a mansion tax to the Finance Bill after the Budget.
Labour sources tell me that this threat will be enacted if the government doesn't allocate time for an Opposition Day debate before the Budget. A source says:
'We want to be clear that we are serious about this. This is a test for the Lib Dems to see if they can keep just one of their promises. It's a test for Nick Clegg as leader.'
The chances are that there will be time for an Opposition Day debate between now and Budget day, especially as the Commons is not exactly chock-full of legislation at the moment. But this is the gift of the Government, not the Opposition. And as I outlined in my earlier post, there are opportunities for the Lib Dems to do something that neutralises the vote, such as an amendment. But far from trying to cosy up to the Lib Dems with similar policies, Labour are trying to make it clear that they don't believe voters should trust Nick Clegg's party. Which is exactly what the Conservatives are doing in Eastleigh at present, too.