Dispatches reveals a new vehicle emissions scandal. Going undercover, the programme investigates how British hauliers are using high-tech 'cheat' devices and computerised hacking to disable the emissions controls on their vehicles, which worsens our air quality, all to save themselves money. A former Government chief scientist has described the hauliers involved as having 'blood on their hands' as experts say the premature deaths of 23,000 people each year in the UK are linked to the types of dangerous gases produced by HGV diesel engines - gases that should be controlled by their emissions systems. Dispatches demonstrates how HGVs that have had their emissions systems modified by hauliers produce far higher levels of dangerous pollutants, by conducting the first ever scientifically controlled test to assess the impact of the 'cheat' devices on the air we all breathe.