“William Ireland, one of the Popish Plot defendants charged with plotting the assassination of Charles II, spoke at trial about his inability to prepare a defense when imprisoned and unaided. He named alibi witnesses who could prove that he was in Staffordshire, far from the scene of Oates’ and Bedloe’s allegations. “[O]n calling his first witness he observed, ‘It is a hundred to one if he be here, for I have not been permitted so much as to send a scrap of paper.’ “87 His witnesses did not appear, and Ireland and his codefendants were convicted and executed.”