This casebook features rigorous analysis of legal doctrine positioned against a backdrop of cultural and political debate. Its core is the act and mental state requirements of both the common law and the Model Penal Code. Topics of current interest include sexual assault, stand-your-ground laws, battered woman's syndrome, the insanity defense, and capital punishment. The chapter on liability for the conduct of another is completely new. It integrates treatment of two doctrinal paths to that result, complicity and conspiracy, beginning with the Supreme Court's 2014 Rosemond decision and combining consideration of other doctrines common to both.