The Assassin's Code states that you must take any job, no questions asked. But you are pretty sure that you have assassinated this target a few times already.

And it wasn't until he noticed you watching him, that you knew the cover you made was blown. He stared you down, and you simply stared back.

You wouldn't be able to take him, not in public. But.. he didn't seem to remember you. You'd, supposedly, taken his life at least 7 times. Yet, he didn't react.