4 ideas
Inspector Alan Grant, immobilised in hospital, investigates the Princes in the Tower using contemporary records rather than chronicles. He finds that Titulus Regius had already declared the boys illegitimate, which removed Richard's motive to kill them. Henry VII repealed Titulus Regius and ordered it destroyed unread, which made the princes legitimate heirs ahead of his own claim and gave him the stronger motive.
A Tonypandy is a false account of an event that becomes accepted history even though living witnesses know it to be untrue. The name comes from a story that troops shot striking Welsh miners, when in fact only police with rolled mackintoshes were involved. Such legends survive because a dramatic, morally satisfying version gets repeated by people who have no stake in checking it, and each retelling adds authority.
Instead of asking whether a story sounds plausible, ask how the people involved behaved afterward, as if the alleged crime had happened. The accusation then probably arose later, from someone who needed it.
Separate records created at the time for practical purposes, such as statutes, rolls, household accounts and letters, from narratives written later by chroniclers. Then ask whether each chronicler was present and whom they depended on. Thomas More's damning account was written by a man who was a child during the events, working from the testimony of Richard's enemy John Morton, and later historians copied it rather than checking it. Its authority is inherited, not earned.