Dr Keith Simpson , the pathologist and firearms expert , was called by the prosecution in the A6 murder case at Ampthill , Bedfordshire . James Hanratty , 25 , is charged with the murder of Michael John Gregsten , 36-year-old physicist of Abbots Langley , at Deadman's Hill , near Bedford on 23rd August . He is also accused of the rape and attempted murder of Miss Valerie Storle . 23rd November 1961