Drink driving is one of the biggest killers on our roads. Brian Suffoletto is an A&E doctor in the US where he's spent the past 15 years developing digital interventions to stop people drinking and driving. Lately he's been working on a system that uses a smartphone to analyse the way a person walks to pick up on subtle giveaways that they're over the limit. Katie Haylor heard how it works... Like this podcast? Please help us by supporting the Naked Scientists