Pennsylvania’s Crimes Code makes it a crime to possess any “instruments of crime.” Instruments of crime include all weapons used in planning or committing crimes. They also include body armor worn or possessed during the commission of a crime and any item “specially made or specially adapted for criminal use.” Even gun parts and guns that do not work but are used in criminal activity qualify as instruments of crime.
The Crimes Code also absolutely prohibits the possession of certain specific weapons designated as “prohibited offensive weapons.” These are items determined to be so dangerous that their mere possession is a crime. It is illegal to own or possess a bomb, grenade, machine gun, sawed‑off shotgun with a barrel less than 18 inches long, or any firearm specially made or specially adapted for concealment or silent discharge.
Also illegal are blackjacks, “sandbags,” and metal knuckles-items used to hit or strike someone with lethal force. Any knife or cutting instrument the blade of which can be exposed in an automatic way by a switch, a push‑button, or a spring mechanism is illegal. It is illegal to own or possess any stun gun, stun baton, Taser or other electronic or electric weapon, or other implement for the infliction of serious bodily injury.
Many of these items are available for purchase in small retail stores or through catalogs but are nevertheless illegal. Certain law enforcers and licensed individuals can qualify to possess some prohibited offensive weapons. The Crimes Code includes a catchall prohibited weapon, defined as any “other implement for the infliction of serious bodily injury which serves no common lawful purpose.”
A Pennsylvania man recently failed to convince the court that his folding knife was not a prohibited offensive weapon. The elaborate folding pocket dagger did not open automatically by a spring mechanism but was designed to lock the open blade in a 90‑degree position. A knife expert who had sold sporting knives for over 30 years testified that the knife had no common lawful or useful purpose. The jury agreed, and the man’s conviction was upheld on appeal.
Criminals who brandish, display, possess, or use firearms in the commission of a crime are sentenced to a minimum of five years in jail, based on the “weapons enhancement” provisions of the Crimes Code. Even nonworking guns can trigger the five‑year weapons enhancement provisions, since the use of a broken or unloaded gun in the commission of a crime has the same intimidating effect on victims as a working gun.
In another case, a man robbed a retail clerk, using an air pistol that looks like a real gun but that only shoots small plastic pellets by air action. The appeals court upheld the five‑year weapons enhancement provisions, noting that real or replica weapons can be potentially deadly.
Before purchasing any weapon or incendiary device, make sure that it is legal. Many defensive items commonly sold in Pennsylvania are illegal.