According to Hagens Berman’s investigations, Mercedes programmed the majority of their diesel models to reduce the vehicles’ illegally high levels of nitrogen oxide when the vehicles were being tested for emissions.

During real-world driving conditions, the affected vehicles emitted illegally high levels of nitrogen oxide. Mercedes' conduct has led to a decrease in the resale value of its impacted vehicles, as well as increases in environmental pollution by emitting dirty diesel emissions.

According to research conducted on the affected Mercedes models powered by diesel-fueled engines, the models are equipped with unlawful, unfair, deceptive and otherwise defective emission controls utilized by Mercedes.

Indeed, testing at highway speeds, at low temperatures, and at variable speeds, indicate a systemic failure to meet emissions standards. Low-temperature testing at highway speeds for example, produced emissions that were 8.1 to 19.7 times the highway emissions standard. The US lawsuit argued that testing at low temperatures at variable speeds produced emissions as high as 30.8 times the standard.