That's bullshit.
Go to a different branch, ask to talk to a banker or customer service, and start to bitch. They CAN tell you in the branch why they debited your account. Ask to speak to the manager, and if they say it's against policy, ask them to print out where in their P&P it says they can't. Oh and bring two forms of ID, just in case, and make sure you don't use your social security card as a form of ID. It's only against the law for banks to give out financial information if you don't have valid ID.