Legislators enact laws, law enforcement personnel execute laws, and, within limits, judges interpret both the laws and their execution. Although this operative concept generally shapes the way we think about the criminal justice system, the paradigm is incomplete. As every law student learns in a professional responsibility or legal ethics course, all members of the legal profession share a responsibility for improving the legal system. Thus, while constitutional and statutory rules provide the structural framework within which legal actors operate, systemic obligations to seek and secure justice–defined, in part, by preventing erroneous convictions-directly inform and guide the entire decision-making process.