Earlier quoted context omitted.
The officer doesn't have to know. Or care. He just takes every penny the system allows and lets you fight the DA over it at a later date. Even if the money is returned, it doesn't cost the cop anything to try. And if they keep the money, some moeny goes back to the police department.
Yes, but my statement was more of a technical one regarding how such a system might work. I am speaking about the method used to determine how much is in an account and what can be withdrawn, because they can't check your balance without a pin number, and if their system is issuing multiple repeated authorizations, what protections banks have in place that might block these sorts of transactions to prevent theft.
Fun fact, when running credit or debit cards you can actually get the available balance on them. I've made the mistake of going to the gas station when my checking account only had a couple of dollars in it, ran the card at the pump and it let me put in exactly enough gas to 0 out my account and no more.