The general principle of equality in European law is often held to be inconsistently applied by the European Court of Justice (ECJ) and insufficiently supported by methodology. Contrary to this assessment, this paper argues that there is substantial coherence and theoretical underpinning to the court's equality reasoning. First, it shows that the respective case-law can be subdivided into three groups, depending on the level of scrutiny applied. Second, it establishes that the prevailing accounts have difficulty in explaining the court's choice of scrutiny due to their limited selection of analytical parameters. Third, it concludes that comparative institutional analysis offers an alternative framework to make the ECJ's testing approaches in equality matters more intelligible.