GM Medical Examiner's Office London Borough of Hackney, Greater London, England Wednesday, April, 1st, 2015 4:15 PM   There was an old expression.  "Why does the Regents Canal run through Hackney?  To avoid getting shot."  Known as one of the most crime-ridden areas of London, Hackney's reputation was not entirely ill earned.  Drug dens and shootings weren't entirely uncommon.   Arsons were for their part far rarer outside of riots.  After the fifth in a recurring series of fires resulted in