"I don't think I'm allowed to talk about that. It is definitely not me. The role has been cast"

This quote by Mary Todd Lincoln suggests that she is not permitted to talk about a specific topic, which the role has currently been designated to somebody else. This might imply that she is not enabled to talk about a certain role or project that she was not chosen for. It might likewise indicate that she is not allowed to review a particular topic as a result of a discretion arrangement. It is possible that Mary Todd Lincoln was asked to audition for a duty, yet was passed by for it. She might be attempting to secure the identity of the person who was chosen for the duty, or she might be trying to safeguard the task itself. Whatever the case may be, it is clear that Mary Todd Lincoln is not enabled to discuss the subject, which the role has already been cast.