Newly unearthed records in a Munich archive have cast doubt on Adolf Hitler's whereabouts at the time of his niece's suspicious 1931 death, according to news magazine Der Spiegel.

Hitler's unusually close and controlling relationship with his niece, Geli Raubal, has long been the subject of speculation and rumor, and newspaper reports at the time suggested that Hitler may have played a role in her death.

Raubal died from a gunshot wound to the chest from a pistol belonging to Hitler, in what was officially determined to be a suicide.

According to the official account, Hitler's personal servant, Georg Winter, discovered the 23-year-old Raubal's body on the floor inside her locked room in Hitler's apartment in Munich on Sept. 19, 1931, a Saturday.

Hitler, who at the time was a prominent far-right extremist but had not yet seized power in Germany, was away in the city of Nuremberg that day, giving him what appeared to be a strong alibi.

But according to an article in Der Spiegel, historian Harald Sandner recently discovered documents in archives in Munich casting doubt on that account — and raising questions about whether Nazi sympathizers in the police may have falsified records to protect Hitler.

Two death notices and an entry in an official local death registry all put the date of the discovery of Raubal's body to Sept. 18, a full day earlier, when Hitler was known to still have been in Munich.

Strange relationship
Hitler's relationship with Raubal, the daughter of his half-sister Angela Raubal, was the subject of intense speculation. Some contemporaries believed Hitler had been abusive or had pursued a sexual relationship with his relative.

Hitler reportedly strictly controlled nearly every aspect of Raubal's life after she moved to Munich in 1927.

She reportedly argued intensely with Hitler just before her death after Hitler refused to allow her to move to Vienna.

Sandner told the magazine the discrepancy in the documents over the date of Raubal's death may point toward a cover-up by the police, though there is no decisive proof.

Days after Raubal's death, a left-wing Munich newspaper reported Hitler had been in a heated argument with his niece, that injuries had been found on her body and that Nazi officials held crisis meetings regarding how to present the matter to the public.

Other newspapers suggested Hitler might have had Raubal killed — or killed her himself — though the Nazi leader publicly denied those allegations in a statement.