This fourth edition of Criminal Law Defences fully updates this classic work. Pat Knoll, Q.C., a former Senior Crown Counsel and defence counsel, now Professor of Criminal Law at the University of Calgary Faculty of Law, draws upon his substantial experience to provide the most comprehensive articulation of the criminal defences available.Prosecutors and defence counsel alike will benefit from this concise, complete and easy to use reference. The foundations of each defence are clearly explained and the recent interpretations of them by the courts reviewed. Criminal Law Defences, 4th Edition is a quick, clear and authoritative exposition of the criminal defences available in Canadian law, including lesser known defences not dealt with by standard texts.Criminal Law Defences, 4th Edition is a unique and indispensable resource for the Canadian criminal law practitioner.