Following the cash-for-amendments scandal of 2011, the European Parliament (EP) reformed and extended its ethics system. The reform was completed quickly coming into effect at the beginning of 2012. This paper examines the nature of the EP’s ethics system that was forged at this time and explains this as a function of an attachment on the part of the Parliament to the norm of parliamentary independence or self-government. The paper situates its argument about the EP parliamentary ethics and independence in a theoretical frame drawing on both institutional theory, democratic representation and legislative ethics. It identifies the nature of the ethics system introduced within the EP on and after 1 January 2012 and charts the process by which the reform was introduced. The final section explains the EP’s ethics system from the perspective of parliamentary independence, while also identifying secondary factors that helped to shape reform outcomes. The conclusion sums up the argument, explains what this research contributes to our understanding of the European Parliament, and suggests how this case might offer a pathway towards more comparative studies of public (and more particularly, parliamentary) ethics.