For instance, if you define that even if every other qualification in the law is met, it's not child pornography if it's one partner in a legal relationship sending another a nude photo, you still have a couple problems: 1) It's legal, as far as I know, for an adult to date a minor less than 4 years younger than him/her in PA, so you'd make it legal for a 14 year old to send nude photos to an 18 year old -- is this acceptable? 2) What about people that intercept the photos, or something of that sort?
This really isn't a cut-and-dry issue, I believe, but something needs to change.