A few years ago in college, I set my friend “James” up on a date with my friend “Erica.” They dated casually for a few months, then broke up. I fell out of touch with James after graduation and chat once or twice a year with Erica. Recently, I heard from someone else that James was in prison and confirmed it with a quick Google search. He’s serving a significant sentence and will be on the sex-offender registry for life. Not saying something to Erica about this feels like a lie of omission. On the other hand, she’s very sensitive and tender-hearted, and I’m worried she’ll be disturbed or even blame herself for not seeing signs that James could be dangerous. I also feel guilty for setting them up in the first place, even though I thought James was sweet when I knew him. Erica lives in another state and isn’t likely to hear this from anyone else. Should I tell her? If so, how? Wait until we see each other again, or send her an email? How culpable am I for trusting my friend’s safety to a person who turned out to be capable of monstrous things? Do I owe Erica an apology?