Background
Ashby (always known as "Mike") was born in London, the son of Arthur Brian Ashby, a barrister and company chairman, and Dame Margery Corbett-Ashby.
Ashby (always known as "Mike") was born in London, the son of Arthur Brian Ashby, a barrister and company chairman, and Dame Margery Corbett-Ashby.
He was educated at Ashdown House Preparatory School and at Oundle School. He studied medicine at New College, Oxford, and at the London Hospital.
After qualifying, he was a house physician before joining the Royal Army Medical Corps, where he served from 1943 until 1947, becoming a medical specialist in 1945. On discharge from the Army in 1947 he worked at the National Hospital before returning to London Hospital as senior registrar to Russell Brain and Ronald Henson. In 1949 he was appointed consultant neurologist to the Whittington Hospital in north London, where he remained until his retirement in 1975.
He succeeded Macdonald Critchley as consultant neurologist to the Royal Masonic Hospital in 1965, also retiring from there in 1975.
He also had a private Harley Street practice which involved much medico-legal work. He gave evidence in the Guenther Podola and John Bodkin Adams murder trials.
His evidence in the latter in 1957 has been criticised for being too indecisive. While fellow witness Doctor Arthur Douthwaite was adamant Adams had killed the victim, Edith Alice Morrell, Ashby was more hesitant.
In summing up, the judge called Ashby "the key witness", one "coming between the extremes", whose "border-line evidence" made it unsafe to convict.
Adams was acquitted of the Morrell charge but was due to be tried for the murder of Gertrude Hullett straight after. The prosecutor, Reginald Manningham-Buller, withdrew the charge however by entering a nolle prosequi - partly because - in his words - the case would again be "based on the evidence of Doctor Ashby". Adams was thought by Home Office pathologist Francis Camps to have killed 163 patients.
In 1944 Ashby married Pamela Mary Roffey.
Their elder daughter, Charlotte, died in a car crash in 1966, the day before her 21st birthday. Ashby was a freemason and director of ceremonies at the London Hospital Lodge.