Power in local government is particularly important to a political party that is in opposition nationally. For a start there is the impact on morale of council election results. Politicians can dismiss (or pretend to dismiss) opinion polls. Real elections cannot be so easily brushed aside. So local elections are taken, quite reasonably, as a rough and ready measure of whether a party is “on course” for a general election victory.

There is also the respite they offer from the inherently depressing nature of opposition. Instead the opposition can point to positive examples of where their policies are being implemented. “We know that this can achieve results because we can already see what is happening in Dudley….” Credibility can be claimed by pointing to a town hall already acting as a “testbed” or “showcase” for a policy.

It can work the other way, of course. Councils can be pointed to as a warning of what would happen if the Leader of the Opposition got into Downing Street. During the 1980s the constant supply of stories about “Loony Left” councils such as Liverpool, Lambeth, and Islington contributed to Labour’s failure to win nationally.

At present we have a bit of a score draw. A typical Labour council is rather dull and managerialist. Even where the Corbynistas have won some selection contests, such as in Haringey, they have yet to make a dramatic impact. But it would be difficult for Labour to generate much enthusiasm for their party in places where they are already in charge. I have already written for this site on the failings of the Labour Mayor of London and the Labour-run Welsh Government. Birmingham is the country’s largest metropolitan authority – Labour are also in power there, but their performance has been pretty dismal.

Yet the “town hall test” should be more instructive than ever. Given that the housing shortage was such an important issue at the last General Election – and is sure to be at the next one as well – the examples of local authorities should offer the electorate a pretty good clue.