A British Court of Inquiry convened on 7 July that year investigated the crash of Sikorski's Liberator II serial AL 523, but was unable to determine the cause, finding only that it was an accident and "due to jamming of elevator controls", noting that "it has not been possible to determine how the jamming occurred but it has been established that there was no sabotage." The Polish government refused to endorse the report, due to the contradiction about the cause not being determined but sabotage being ruled out, and pursued its own investigation, which suggested that the cause of the accident cannot be easily determined. The political context of the event, coupled with a variety of circumstances, immediately gave rise to much speculation that Sikorski's death had been no accident, and may have been the direct result of a German, Soviet, British, or even Polish conspiracy.
