If Oxford City Council ’s legal department were not expecting trouble they should have been.

The city council this week stands accused of introducing an illegal local tax, which risks not only souring relations with both universities for years but will see land values in the city plunging.

As we commented last month, the city’s proposal to make those behind student accommodation schemes contribute towards affordable housing in the city was designed with worthy intentions: to get developers building more family homes rather than student flats.

Unfortunately the potential impact on our two universities looks to have been (let’s be kind) rather underestimated. But a pattern seems to be developing — whether we are talking about creating a new community by the ring road or restricting the number of students living in residential communities — with well-intentioned council policies emerging as legally-questionable plans.

Once more the city is faced with making some frantic changes to avoid the risk of another humiliation at the hands of a planning inspector.

No one at the Town Hall can surely relish returning from their summer holidays to face a public inquiry dust-up with university barristers over the legality of a policy that both universities says will hinder their future development. The fact the affordable home charge policy was introduced ten months before it was due to go before an inspector, shows a confidence that is looking more misplaced by the day.