Princes in the Tower "the murther of his nephews towards the world", indicating that the boys did indeed meet their end during Richard's days. It is also unlikely that the princes would have been kept alive in secret by Richard for 2 years after their last sighting while rumours of his responsibility for their murder circulated. Some writers have also accused John Howard, 1st Duke of Norfolk; Margaret Beaufort, Henry VII's mother; and Jane Shore (Edward IV's mistress). Pollard writes of these theories: "None deserve serious consideration. The problem with all these accusations is that they beg the question of access to the Tower
Princes in the Tower implicated in the decision to murder them, the hypothesis that he acted without Richard's knowledge is not widely accepted by historians. While Jeremy Potter suggested that Richard would have kept silent had Buckingham been guilty because nobody would have believed Richard was not party to the crime, he further notes that 'Historians are agreed that Buckingham would never have dared to act without Richard's complicity, or at least, connivance'. However, Potter also hypothesised that perhaps Buckingham was fantasising about seizing the crown himself at this point and saw the murder of the princes as a first step to achieving this