AT Lanchester, in County Durham, the A691 has a 30mph speed limit, sensibly so.

Turn right up the A6076 Howden Bank – a steep hill – and the signs indicate end of restriction, with a dual-carriage way up the hill (a crawler lane for buses and lorries) and single carriageway down.

Higher up the road, throughout 2006, 2007 and 2008 there were 30mph signs hidden by the hedge or trees or bushes.

The signs were simply not visible.

Police with radar guns hid in The Crescent and handed out a lot of tickets, gained a lot of convictions and gathered a lot of revenue.

A motorist challenged this, refusing the fine and electing for a trial.

Prosecution offered no evidence, case dismissed.

The local highways department then remedied the defect. The money-gathering game was up.

I would doubt whether the hundreds who’d been fined over the years could get their convictions quashed, their fines refunded together with extra insurance premium (about £90) that they’ve had to pay.

It would be grossly unfair otherwise.

Richard Camidge, Leeds.