This paper presents a critical analysis of the Financial Market Commission’s decisions that apply a criminal provision of the Financial Market Act to administratively declare and sanction criminal conducts. This practice involves an undue exercise of jurisdictional functions by an administrative body that infringes the principles of separation of powers, due process, and the logic underlying administrative responsibility in regulatory matters. The violation of these basic tenets of the rule of law also affects the citizens’ right of access to natural justice, and the principles of legality and proportionality.