Jeremy Heywood’s resignation gives Theresa May’s government an unexpected legacy

The departure of one of Whitehall’s pre-eminent officials has a surprise implication for Theresa May.

Jeremy Heywood, who for close to three decades has been close to the epicentre of British government, has resigned his post as Head of the Civil Service on medical grounds: Heywood had to take a temporary leave of absence due to a cancer diagnosis, and while he will receive the customary life peerage for a departing Civil Service chief, his main focus, at least in the short term, will be on his health.

So although his resignation message includes a sideswipe at the “anonymous commentators” (read: Brexit ultras in the Conservative party and the right-wing press) criticising civil servants, this isn’t, unlike the exit of Ivan Rogers from the Civil Service, a departure driven by politics and personality clashes. Indeed Heywood was one of the civil servants who was able to work with Theresa May, whose working style has not always been easy for civil servants to adapt to anymore than it has been for ministers or special advisors.

But his departure means that May’s premiership will have a more lasting impact on the structure of Whitehall than expected. Almost no-one now privately defends May’s 2016 Whitehall re-organisation, which cleaved Brexit off into the Department for Exiting the European Union (Dexeu) and created a free-standing Department for International Trade (DIT). (The one exception are officials at the Foreign Office, who while initially bruised to be cut out of the biggest foreign and domestic policy challenge since the Second World War, are now quite cheerful about having escaped the paralysis and acrimony of Brexit while still being able to focus on other things.) It’s widely expected that sooner or later, DIT and Dexeu will be folded in other departments, with a trade minister who has full Cabinet rank but sits in the Foreign Office in the manner of the Chief Secretary to the Treasury, the Treasury’s second Cabinet minister.

There will, however, be a lasting May legacy, but it will have a face rather than a department: Heywood’s replacement Mark Sedwill, who is widely respected on Whitehall but who colleagues concede also had the good fortune to be both qualified and able to work with May and her combative former chiefs of staff, Nick Timothy and Fiona Hill.

Now Sedwill is Head of the Civil Service where he will have an understated but vital role at the heart of the British state: ironically a more lasting legacy than anything else Theresa May has done will have.