I was thinking about immigration and the complaint that some people have voiced that allowing those who have come here illegally, but have families, to somehow gain citizenship, ‘encourages’ people to cross the border illegally.

Contrast that with stand your ground laws. See http://www.npr.org/sections/thetwo-way/2017/03/10/519664502/judge-rejects-stand-your-ground-defense-in-florida-theater-shooting-case

There probably is a valid argument that both encourage behavior, however I think it is clear that one of them has a worse outcome than the other.