Stopping Over-Criminalization Act of 2015

This bill amends the federal criminal code to establish a default mens rea (guilty mind) standard for a federal criminal offense, unless the provision of law that defines such offense specifically provides otherwise.

A federal criminal offense conviction requires proof that a defendant acted knowingly with respect to each element of the offense. If a defendant might lack reasonable awareness that conduct (e.g., a regulatory offense) is criminally punishable, then a conviction requires proof that the defendant had reason to know the conduct was unlawful.

Additionally, the bill amends the federal judicial code to: (1) require the Department of Justice to develop, publish, and update an inventory of all federal criminal offenses, including agency rules that carry criminal penalties; and (2) prohibit prosecuting a defendant for a non-inventoried federal offense.

Finally, it amends the Congressional Review Act to require congressional approval by joint resolution for a new rule with criminal penalties to take effect.