The man who hanged himself at the age of 93 in Berlin's Spandau Prison in 1987 really was Rudolf Hess, Adolf Hitler's former deputy, DNA tests have confirmed, quashing a conspiracy theory that persisted for more than 70 years. Researchers trying to prove that the Nazi was not replaced by a doppelganger tracked down a Hess relative in Germany and compared his DNA to a blood sample provided by Spandau's Prisoner No. 7 in 1982, the New Scientist reports. Testing revealed that there was a match of almost 100%. Conspiracy theorists, including W. Hugh Thomas, one of the doctors who treated Hess in prison, had suspected that an impostor replaced Hess before he flew to Scotland in 1941 in an attempt to negotiate peace with Britain.
Hess was captured on arrival in Britain. He was sentenced to life in prison at the Nuremberg trials in 1946 and transferred to Spandau in 1947. Thomas claimed that the man he treated had physical differences from Hess, the BBC reports. He also found it suspicious that the prisoner's family refused to see him for years. Former US Army pathologist Rick Wahl, one of the authors of a study in Forensic Science International Genetics, had kept the blood sample on a slide for teaching purposes and it proved to be very useful—Hess' body was exhumed and cremated in 2011 to prevent his grave becoming a pilgrimage site for neo-Nazis, meaning the slide held the only known scrap of the Nazi's DNA. (A dossier that surfaced in 2013 answered questions about his 1941 mission.)