I wanted to clarify that in my responce I should have said that you should go right away and
open a new account at a different bank
re-direct any direct deposits to the new account
leave just enough money in the old account to cover outstanding checks/charges
If you totally empty the old account they could use that against you saying that you were trying to scam the bank out of the money. When the check does come back as conterfeit and they take that $5000 out, and your account is down to nothing,
THEN if you would like to get a lawyer you can do that to fight the bank over that $5000, or you can call it a learning experience and close that account.
Also, I have been told by someone in the banking system that it could take 3 months or more for the check to come back as counterfeit and the customer would still be liable. If you have open a new account, and stopped doing regular business with the old bank, then you are just in a waiting game until the bank finds out that the check is counterfeit. There is not much you can do, but at least you know that you have money in another account that they cannot touch and you can continue to live on (others have had all of their bank accounts locked up because they only had the account at one bank)