Fairness in Firearm Testing Act This bill amends the Homeland Security Act of 2002 to direct the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) to make a video recording of its entire process of examining and testing an item to determine whether it is a firearm (and if so, the type of firearm) or ammunition. The bill bars the ATF from editing or erasing any such recording. The ATF must make a digital video disc containing a copy of the recording available to: (1) a person requesting a copy who claims an ownership interest in such item, and (2) a defendant in a criminal proceeding involving such item. An item which the ATF has determined is a firearm or ammunition shall not be admissible as evidence unless: (1) the ATF has complied with the requirements of this bill to make its digital video disc available, or (2) such compliance has been waived in writing by the person against whom the item is offered as evidence.