A raft of excuses ("battery's dead") and security problems come to mind; how would you implement such a system?
Not to worry, I have a phone charger with all the right attachments back in my cruiser. "Phone charging", quote on quote, is part of the many services we provide.
Believe it or not, I even have this handheld $20,000 gizmo that can back up the content of your phone in less than two minutes, whatever brand of phone you use. It also helps that SSD memory, by design, doesn't try to overwrite its memory spaces of deleted pictures with newly taken pictures, unless it's absolutely necessary. It's a way to make the SSD memory more reliable.
So if you're phone is not completely full, I may even find pictures that you deleted more than two years ago. Are you sure you don't want to tell me what illegal activity is on that phone, before I discover it myself. I'd go a lot easier on you if you told me now, instead of just wasting my time. After all, we both know I'm going to find out what you're hiding on that phone eventually, and then you'll be in hell of trouble.