  This "blue sky idea" paper outlines the opportunities and challenges in data
mining and machine learning involving making a computational attorney -- an
intelligent software agent capable of helping human lawyers with a wide range
of complex high-level legal tasks such as drafting legal briefs for the
prosecution or defense in court. In particular, we discuss what a ChatGPT-like
Large Legal Language Model (L$^3$M) can and cannot do today, which will inspire
researchers with promising short-term and long-term research objectives.
