The next Tory leader will have even less flexibility than May on Brexit

In Choosing A Leader, what remains one of the best books published on British leadership contests (although I appreciate this is a niche market), Len Stark argued that the procedures parties used when selecting their leaders rarely made much of a difference. With a handful of exceptions, he demonstrated that the same candidate would have won, no matter how the party went about making its choice. Parties chose candidates who will unite them, he argued, after which what mattered was who was most electorally appealing or most competent – and they did that regardless of the rulebook.

Yet there were exceptions, not all of them inconsequential. Stark’s book was published in 1994, and even then the outliers included the 1975 contest from which Margaret Thatcher had emerged victorious. A more recent list of exceptions would also have to include Jeremy Corbyn’s victory in 2015.