Yeah, but it's not that simple. You'd have to install the Tor Browser Bundle, make it look like it was installed long before. You'd have to change the MAC times on the CP files to indicate a consistent pattern, and make sure the victim doesn't have an alibi for any of the times you're putting down. But you can't backdate the download time to before the image was produced, so you have to do your research on that. And of course you'd have to get your hands on a bunch of CP without getting caught yourself.

I'm not saying it's impossible, but it sounds pretty difficult to me. Maybe I'm wrong though.