The report, prepared for Transport for London by King's College London's Environmental Research Group, predicted that the charges would create a "very high disbenefit" not only for CO2 but also for NOx, NO2 and particulate matter. The reason cited for the increased emissions is that drivers will choose to drive around London instead of driving straight through, which would be a much shorter trip. London's emissions may drop, but the surrounding areas will be disproportionately hurt.
According to Andy Goss, Managing Director of Porsche Cars GB, "We always knew the environmental impact of this unfair tax would be minimal, now we know it will make matters worse. The Mayor and TfL need to explain why this report was not disclosed and why they want to increase taxes on motorists that will increase CO2. It seems absolutely clear that the report shows that not only have Mayor Livingstone and TfL not presented all of the information to the public about the impact of his £25 charge, but that they have also created a new tax on motorists that will do the exact opposite of its stated goal." Read more of Porsche's response here.