The scale of Brexit resignations is now so great that Theresa May could run out of potential ministers

When people say the first rule of politics is to be able to count, it usually means keeping track of how many people are likely to vote with you and against you in the sorts of votes that have punctuated the parliamentary timetable in recent weeks. But increasingly, an abacus and advanced arithmetic are necessary to keep up with the resignations from Theresa May’s government. The scale of the problem is obvious and the implications for good government quite serious.

There are as many eye-opening stats to choose from as indicative vote options. In her two years and eight months as prime minister, May has faced 28 ministerial resignations outside reshuffles, more than Margaret Thatcher did in her 11 and a half years in Number 10. Twenty-seven have come since the 2017 general election, with 20 of them due to policy or political disagreements—more than under Blair, Brown and Thatcher put together. Eighteen of those resignations have been because of Brexit, including four from the cabinet.

Between 1979 and 2017, only once did three ministers resign in the same twenty-four hour period (Carrington, Atkins and Luce over the Falklands). This has happened three times since the start of 2018—three ministers in July 2018, four in November 2018, and three this week—because of Brexit.

The departures of Steve Brine, Richard Harrington and Alistair Burt—who all resigned this week—has created four ministerial vacancies (Burt spanned both the Department for International Development and the Foreign Office). But there is a fifth vacancy—Sarah Newton quit as minister for disability at the Department for Work and Pensions on 13th March but had still not been replaced a fortnight later. Junior ministers might not always attract headlines, but their work—driving policies through their departments, doing much of the heavy-lifting in parliament—matters. Disability charities have been outragedat the lack of a replacement for Newton.

David Cameron replaced all of his resigning ministers within 24 hours; May has long been reconciled to taking considerably longer. The situation with Newton is not unique—it took weeks to replace Damian Green, then de facto deputy prime minister.

This reflects the political challenges of the post-referendum landscape, but it may also be a sign that the pool of potential replacements is running dry.

As the prime minister looks to fill vacant positions in her government, she may first look to promote those serving their ministerial apprenticeships as parliamentary private secretaries—unpaid aides to ministers or ministerial teams. This is less the first rung on the ministerial ladder than the ground beneath it. But 11 of these roles that were previously filled—including the PPSs to the Secretary of State for Housing, Communities and Local Government, and to the ministerial team at the Department for Exiting the European Union—appear to be vacant.

If she turns to her backbenches, the PM finds less a pool of talent than a puddle. The nature of a minority government means she already has fewer MPs to choose from than many of her predecessors. The nature of the political divisions brought by Brexit means that, as of the beginning of March, only 25 Conservative backbenchers hadn’t rebelled against the government. Of these, two are currently chairs of select committees, 14 are former ministers, and many of the others are veterans who might already have expected ministerial office had they sought it.

The prime minister has already had to appoint former ministers to new roles. Two of the three most recent appointments are so-called “retreads”—Robert Goodwill, reshuffled out of government by May in January 2018, and Chris Skidmore, reshuffled out of government and into a Conservative Party vice-chair role at the same time, have both returned in recent months.

Some ministerial careers might have been extended by Brexit—would Chris Grayling have survived in more normal political times? But on the whole, Brexit has jammed the conveyor belt of ministerial succession. Minority government, Brexit divisions within the Conservative Party and an unprecedented number of resignations have all narrowed the prime minister’s options. Ministerial posts as well as more junior ones remain unfilled, complicating the conduct of government.

It is a one way revolving door, with the number of ministers resigning continuing to increase as the number of those who could replace them diminishes. With more votes to come in parliament, there could yet be more resignations. Who can the prime minister count on to replace them?