Professor Heffernan has taught John Jay for more than 30 years.  During that time, he has served as program director of the master's degree program in criminal justice and as an editor of Criminal Justice Ethics, a publication of John Jay's Institute for Criminal Justice Ethics.

His books include Privacy and the American Constitution: New Rights through Interpretation of an Old Text (Palgrave 2016) and Dimensions of Justice: Ethical Issues in the Administration of the Criminal Law (Jones & Bartlett 2014).  Among his edited books are From Social Justice to Criminal Justice: Poverty and the Criminal Law (Oxford 2000) and Police Ethics: Hard Choices in Law Enforcement (1985).  

His articles on constitutional criminal procedure have appeared in the Journal of Criminal Law and Criminology, Georgetown Law Journal, Wisconsin Law Review, Notre Dame Law Review.