New research by Channel 4 reveals that 123 MPs – just over one fifth of the total – let out at least one property to supplement their income.

The MPs include chancellor Philip Hammond, Boris Johnson, the shadow foreign secretary Emily Thornberry, and the Speaker of the House of Commons, John Bercow.

Channel 4’s FactCheck research service admits that the figure may not be 100 per cent correct as, firstly, there is no definite check on the MPs’ register of interests so the presumption is that members are declaring honestly; second, it is not illegal for an MP to not declare a financial interest; and thirdly, MPs are only asked to declare properties which they earn more than £10,000 a year from. 

Under the declared figures, some 28 per cent of Conservative MPs are landlords, 11 per cent of Labour MPs, nine per cent of SNP members, 25 per cent of Lib Dems, and 10 per cent of the Democratic Unionists – the latter party supporting the Conservatives to form a majority in the current House of Commons.

In the last parliament, many MPs who let out property were criticised for contributing to votes seen as supporting landlords. Most famously, says FactCheck, 72 landlord MPs were among those who voted down requirements on landlords to ensure that homes are “fit for human habitation” in a Private Member’s Bill last year.

A version of that Bill, from Labour MP Karen Buck, is going to be debated in the House of Commons early next year. 

FactCheck says: “Clearly, there is the potential for a conflict of interests. MP landlords can vote on housing legislation, speak in debates and hold ministerial positions, so long as they declare their interests. But are MPs actually swayed by their financial affairs in any sizable numbers? Putting figures to this is incredibly hard.”