The researchers analyzed how the European Union's carbon emissions trading program, known as the EU Emissions Trading Scheme, affects carbon emissions in Germany. They found that because this trading scheme covers only part of the country's emissions, additional policies are needed to reduce emissions from sectors not included in the program. By looking at Germany specifically, they discovered that combining the trading scheme with other carbon reduction efforts can lead to decreased efficiency in achieving emission goals. This inefficiency becomes more significant when considering the current distributional limitations of the EU-ETS.