A Swiss motorist who was caught by the Swiss police with insufficient tread depth on his car tyres has been banned from driving for a month, following the decision of the federal court in Lausanne. This ruling by Switzerland's highest judges corrected a lighter sentence made earlier by an administrative court, deciding in favour of clear punishment in the case of unsafe tyres on vehicles.

At the hearing on 7th August, the court was told about a commercial driver who had been stopped in May last year in the course of a police check in wet, rainy weather. The tread depth on the motorist's tyres was in part below the minimum specified limit of 1.6mm. According to the federal judges, this was something the driver would have been able to see and he should have replaced the tyres. Driving around with worn tyres was considered to be a moderately serious offence, as it posed a danger to others.

In the rain, tyres with insufficient tread depth are unable to adequately disperse the water from the ground contact patch and therefore tend to aquaplane as well as to require longer braking distances in the wet. Tyre experts at Continental recommend replacing tyres as soon as the tread depth goes down to three millimetres. Only then can tyres provide adequate safety on wet roads. They also warn that at the same time motorists need to adapt their speed to suit the driving conditions.