The system relies on valuations from 1991, when Gorbachev was in power, but has become politically untouchable

“It’s a fairness thing. Just the idea that somebody sitting in a two-bedroom house in Hartlepool is paying more council tax than somebody who’s living in a mansion – it’s just offensive.”

The Labour backbencher Jonathan Brash, Hartlepool’s MP, is on a mission to draw attention to an issue he jokingly calls “the third rail of British politics” – because no mainstream party, including his own, wants to touch it for fear of electoral death.