Princes in the Tower becoming king, Henry married the princes' eldest sister, Elizabeth of York, to reinforce his claim to the throne. Not wanting the legitimacy of his wife or her claim as heiress of Edward IV called into question, prior to the marriage he had repealed the "Titulus Regius" which had previously declared the princes (and Elizabeth) illegitimate. Markham suggests the princes were executed under Henry's orders between 16 June and 16 July 1486, claiming that it was only after this date that orders went out to circulate the story that Richard had killed the princes, and that the princes' mother, Elizabeth Woodville,
Princes in the Tower acted alone. First of all, if he were guilty of acting without Richard's orders it is extremely surprising that Richard did not lay the blame for the princes' murder on Buckingham after Buckingham was disgraced and executed, especially as Richard could potentially have cleared his own name by doing so. Secondly, it is likely he would have required Richard's help to gain access to the princes, under close guard in the Tower of London, although Kendall argued as Constable of England, he might have been exempt from this ruling. As a result, although it is extremely possible that he was