Growing numbers of motorists are being fined for driving into Scotland's city-centres - according to new figures which call into question the value of the country's controversial low emission zones.

Experts have warned of a 'concerning' trend of teens inhaling nitrous oxide - or 'hippy crack' - before getting behind the wheel, with the reckless act leading to multiple deaths in recent years.

Four years after the tragic death of Xander Irvine, a three-year-old boy killed after an elderly car driver in Edinburgh lost control of her vehicle, the law governing older motorists is under fresh scrutiny.