Question: When did the suspected serial killer to which John B. Harman was notable as a medical expert witness for his defence died? 
Sentence (from "John B. Harman"): John Bishop Harman, FRCS, FRCP (10 August 1907 – 13 November 1994) was a British physician, president of the Medical Defence Union and chairman of the British National Formulary.
Relevant evidence: No