For this answer, I can do no better than to summarize the analysis of Australian National University professor of strategic studies HughWhite in his new book, The China Choice: Why America Should Share Power (2012 Black Ink Books, 191 pp.).
Home Office pathologist Dr HughWhite, told the jury that Mr Millar died as a result of a stab wound through the back of the chest into the left lung which caused severe internal bleeding.