There were rumors put about at the time, certainly false but pernicious nonetheless, by both Mary's and later James's enemies that James was the son of David Riccio. Darnley himself was taunted with this by the conspirators who gained his participation in their murder of Riccio. It was a matter of great import at the time, because it was considered essential for Mary's cause that Henry publicly acknowledge that the infant James was his son, which he did. Caroline Bingham addresses this in her excellent biography of Darnley, as does Pauline Croft in her biography of James VI & I, in which she discuss the way in which it was used against James by those at Elizabeth's court who opposed his succession to the English Crown.