Car manufacturers in the UK are facing a massive legal battle over alleged emissions cheating. The core accusation is that they installed software to manipulate emissions tests. This software, known as "defeat devices," would reduce harmful emissions during testing. In actual driving conditions, the vehicles emitted much higher levels of pollutants. This deception was designed to prioritize customer convenience and sales over environmental regulations. The lawsuit involves approximately 1.6 million diesel car owners. The total damages sought could potentially surpass $8 billion. The trial targets five major manufacturers: Mercedes, Ford, Renault, Nissan, and Peugeot/Citroen. The judgment will also impact numerous other car brands. The trial's primary focus is on vehicles sold starting in 2009. The case is considered the largest group action trial in England's legal history.