The married couple’s tax allowance is back on the agenda. After Conservative Home’s exclusive yesterday, David Cameron has confirmed that he will introduce one before the end of this parliament. This would allow couples to share a proportion of their personal allowance, lowering the tax bill for those household where one person stays home to look after the children.

Cynics will suggest that this is a good time to float a policy particularly popular with the party base given that there are county council elections on Thursday. But Cameron is a bigger enthusiast for recognising marriage in the tax system than most of his Cabinet colleagues. In opposition, George Osborne always worried that it looked like a measure designed to encourage mothers to stay at home. For their part, the Liberal Democrats have the right to abstain on the matter under the coalition agreement.

But it is becoming politically imperative for Cameron to introduce this measure. It would fit with his aim of reuniting the Conservative party before the next election campaign. It would also assuage some of the anger of stay at home mothers who feels that the childcare tax break shows that the coalition is trying to push women back into work.

Given that the coalition agreement is going to become ever more frayed as polling day approaches, introducing it sooner rather than later is going to be necessary. If Cameron waits until less than a year before the election to have a vote on it, he might find the Liberal Democrats far more inclined to actually vote against it rather than just abstain.

Tags: Coalition, Conservatives, David Cameron, Elections, George Osborne, Marriage, Tax, UK politics