Wis. Stat. § 221.0325: Certified checks.

An officer, employee or agent of a bank may not certify a check, draft or order drawn upon the bank unless the person, firm or corporation drawing the check, draft or order has on deposit with the bank at the time the check, draft or order is certified an amount of money equal to the amount specified in the check, draft or order. A check, draft or order so certified by the duly authorized officer, employee or agent is a valid obligation against the bank.