Apart from the fact that this is just a massive Big Brother move, it's also so easy to abuse. Imagine a psycho ex decides you need to suffer forever. All they need to do is email you a photo. Your phone downloads it automatically. You don't even need to open it and look at the email, let alone the attachment - and all of a sudden you've got the police knocking down your door. Even if you manage to clear it up, you're now on a list somewhere until you die.