Would you tell on someone you saw trying to steal a DVD?

Question

I saw a teenager at the local library trying to tear off the bar code from a DVD (the thing which sets off door alarm). I told the librarian. What would you do?

Answer 1

I would'nt tell on him but I probably would confront him about the theft in private.  I suppose once the librarian found out, then he got kicked out of the library.