FFC are frequently asked to review the work instructed by the prosecution classifying air guns as firearms and whether or not they exceed the limits laid down in the Firearms (Dangerous Air Weapons) Rules 1969. Recent criticism in 2015 by the Home Office Forensic Regulator of how in-house Police Armourers go about this task has brought the requirement for rigorous and scientifically sound methods to be in place. FFC has a proven track record in this area and in challenging poor police work. FFC can also assist in the interpretation of section 5(1)(af) of the Firearms Act 1968, the provision that prohibits self-contained gas cartridge air guns and which carries a mandatory minimum 5 year term of imprisonment, bringing to bear recent case law as to the correct legal classification