A bank is not legally required to refuse your money until you can prove you haven’t stolen it. A bank maintains very specific set of government mandated processes where if think something is suspicions they report it to the authorities.

Note the difference (1) if you deposit $50 the bank by default assumes you didn’t just murder someone and take their money, this is true even if you served a sentence for that crime and (2) the bank defers to the government on what to do, they’re not expected to run a parallel justice system figuring out who’s worthy for a bank account