"The problem is that the police has access to it."
So, you don't trust police. Buy an AR-15 and hide in the woods. then.
I understand there are a lot of morons in the police too. There are also good people who pursue true criminals respecting the law.
Would you like a world without law enforcement? Where only the powerful ones can enforce their own rules? And do you believe they will respect your rights to privacy, property, and life?
It's this anarchism that is destroying the foundation of democracy, and sends people like Trump to the top spots - and eventually you'll get exactly what you feared.
"unfeathered access to people's belonging" is against the law. "Planting evidences" too. And if they don't abide to the law, they can plant evidences outside your devices as well.
It can happen? Sure. Wearing a tinfoil hat won't save you - act to ensure democracy stands and it's not turned into a parody of it.