Why should Adam Lanza have undergone a background check? It wasn't his weapon, it was his mother's.  He murdered her in order to gain access to it.  Are you suggesting that every member of a family should have a background check for one member to own a gun?  Would that be just the immediate family? Or should we check the extended family, as well?  All the in-laws?  How about the neighbors? Should we check just the ones who live on the same block, or maybe everyone in a 10 block radius?

When you say "simple," I assume you're referring to your thought processes.