Unless you’re clever about setting up the phones to match your excuse, you are now lying to the police as well.
I think this is the time to share this classic PSA about why you should always exercise your right to silence:
You're not lying to the police in this situation if you've ever done anything ever remotely related to work on the "faux" phone only. That is still considered the "whole truth" in that scenario and would be easy to defend. It's absolutely absurd we need to even think ahead like this, but cops are (mostly) dumb enforcement. They don't actually know the laws in-depth and in many cases do not abide by them - which is the root of labeling them as such. Beating a cop at the game they're playing is not hard, you just have to know every question they ask is loaded and for a reason.
It's crazy that the police can lie to you.
By rights the simple comeback is they can lie to you so F'em.
The real answer is you don't offer any explaination because it's not something you need to explain or get anyone's permission for.
Feel free to wonder. Give me a hard time and I'll just do my best to give you a hard time back. After you confiscate my stuff and detain me and I turn out not to have broken any laws, I'll do everything I can think of to extract an apology and compensation and penalty. Afro Man is my hero. You will become my new career.
That's my little fantasy anyway but I do see it as a duty to at least resist a little. In reality I'll fold pretty easy but I will be as much sand in the gears as I can.
depending on where you are it may be legal to lie to the police.
Incorporate and have the phone be owned by your corporation. You're a contractor who separates business from pleasure.
Follow the usernames in the response chain. I have two phones for the exact same reason as well: work issued & personal. It would hold up just because it’s actually true. There’s no need to arrange anything beyond how they are naturally arranged.