The Lisbon Treaty has consumer protection as a shared competence.
See Article 4 TFEU and 169 TFEU.
Consumer policy is decided by a qualified majority in the Council and co-decision with the European Parliament after a proposal from the European Commission.
Member states are free to impose a higher level of protection than set out in the common minimum EU rules, but all national rules must comply with the rules and principles of the Internal Market. Any conflict may ultimately be resolved by the EU Court in Luxembourg.
The European consumers are organised in BEUC.
Directorate General for Health & Consumer Protection http://ec.europa.eu/consumers/index_en.htm
Activities of the European Union: consumers http://europa.eu/scadplus/leg/en/s16000.htm