Illegal possession of a firearm

Criminal possession of a weapon is the unlawful possession of a weapon by an individual.

Many societies both past and present have placed restrictions on what forms of weaponry private citizens (and to a lesser extent police) are allowed to purchase, own, and carry in public. Such crimes are public order crimes and are considered mala prohibita, in that the possession of a weapon in and of itself is not evil. Rather, the potential for use in acts of unlawful violence creates a perceived need to control them. Some restrictions are strict liability, whereas others require some element of intent to use the weapon for an illegal purpose. Some regulations allow a citizen to obtain a permit or other authorization to possess the weapon under certain circumstances. Lawful uses of weapons by civilians commonly include hunting, sport, collection and self-preservation.

Criminal possession of a weapon generally falls into one of several categories:

All weapon possession crimes follow some standard of intent (mens rea), though this standard varies. The most common is "strict liability," meaning that there is no requirement of intent whatsoever: Merely being caught by law enforcement with the weapon in question under the circumstances described in the law (possession, concealed, or open) is a crime in and of itself, with almost no possible defense other than proving the item is not an illegal weapon within the law's definition. Some laws allow the accused a defense to the charge that the item in question was going to be used for a specific set of lawful purposes, such as one's occupation (examples are sets of knives carried by a line cook en route to his job, or tools carried by a construction worker or craftsman). In this case, the burden of proof is often placed on the accused, requiring them to prove their lawful intent in court.

Other laws require proof of specific intent to commit a criminal act by the accused, thereby placing the burden on the state to produce evidence that the weapon was possessed with some unlawful purpose (such as an attempted homicide, robbery, or assault). The circumstances under which law enforcement discover the weapon often play a strong role in this.

Many laws about weapon possession contain exemptions for persons of specific occupations, or allow for permission to be obtained from the government to lawfully possess the weapon.

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