image credit: Jonathan Thorne cc
Just the thought of cannibalism, or the eating of human flesh, induces shudders in the living. However, most people would agree that as strong as the cultural taboo is, cases in which people ingested corpses because it was the only available food in order to survive can be forgiven (if not forgotten).
The most famous example in American history is the Donner Party, a group of snowbound pioneers who may have resorted to eating their deceased members in 1846-47. On the other hand, those who murder and then eat their victims are viewed with particular horror and contempt.