In 1963, Barschel was among a group of Geesthacht students who attended a school assembly which featured former admiral and convicted war criminal Karl Dönitz, speaking at the invitation of a pro-Nazi history teacher.

The event, during which Dönitz gave an apologia for Nazi ideology with no rebuttal from students and staff, caused a furore when it was reported by the West German and international press.

[5][6] Barschel's autopsy uncovered a total of eight drugs in his system, including the sedatives lorazepam, diazepam, diphenhydramine, and perazine, along with the barbiturate cyclobarbitone and the sleep aid pyrithyldione.

[7] Various mysteries around Barschel's death are discussed in a January 1995 Washington Post article[8] based on German, Spanish and Swiss police investigations of the murder, and the possible motives for it.

[8] On 12 June 2011, the Public Prosecution Department of Lübeck announced that the Barschel case would be re-opened and re-examined, with more sophisticated techniques such as DNA profiling being employed to find out the actual circumstances of the politician's demise.