The Conservative Party is accusing its Coalition partners, the Liberal Democrats, of playing “Westminster tricks” by scuttling a backbench Bill supporting an in/out referendum on the EU – but it seems more likely that the Tories’ own politicking is to blame.

The Yellow Party has retaliated by claiming the Tories were attaching “ridiculous conditions” to the Bill that made it unsupportable, and this seems much more plausible in the light of David Cameron’s reaction to the Scottish referendum debate.

Remember the morning after Scotland voted to stay in the UK? Cameron stepped up to the cameras and promised to deliver the new powers to Holyrood that he and the other UK political leaders had promised – as part of a package that included devolution for England.

Nobody had asked for English devolution to be included. He just inserted it into the deal unilaterally, provoking protest from many quarters (on the reasonable grounds that English devolution is an attempt to ‘lock in’ Tory control over England). This made it possible for him to claim that these protesters were holding up the devolution process when in fact he was the one who had thrown a spanner in the works.

Now it seems he has done the same with the EU referendum Bill. The Liberal Democrats had agreed to support a ‘money resolution’ to approve the costs of the referendum, in exchange for an agreement by the Tories to do the same for a Lib Dem backbench Bill that would modify the bedroom tax.

But the Tories had then insisted that the referendum Bill should be debated in time normally reserved for government, rather than backbench, legislation. The Lib Dems quite correctly rejected this as inequitable.

And didn’t the Tories squeal about it! Bob Neill, the former minister who sponsored the backbench Bill, which came third in the ballot for debating time and is therefore struggling, said the Lib Dems had done “everything they could” to prevent a referendum: “The Lib Dems have killed off our chances of putting into law, this side of an election, an in/out EU referendum by 2017. They didn’t have the guts to vote against an EU referendum in the House of Commons. Instead they have used Westminster tricks to try to deny the British people a say on their membership of the EU.”

In fact, the evidence suggests the only Westminster tricksters in this case are the Tories. And here’s another one: Mr Neill said the Liberal Democrats would be held to account by voters at the next election.

He knows – and we know – that public opinion of the Liberal Democrats has plummeted. They are currently polling behind the Green Party – not because of their attitude to any EU referendum (most of the public couldn’t care less about the EU) but because they have supported a Conservative government whose policies have been compared with those of 20th century fascists – if not Nazis.

The Tories must think we are stupid if they expect us to ignore the fact that they are the ones playing “Westminster tricks”.