Gun Laws Every Owner Should Know: Federal and State Basics

Firearms law in America is a complex web of federal statutes, state laws, local ordinances, and court decisions. You don't need a law degree, but every gun owner needs to understand the basics. Ignorance of the law is never a defense — and firearms violations carry serious consequences. Here's what you must know.

By Dwight Ringdahl — GunExpos.com

Federal Law: Applies Everywhere

Who Can Own a Firearm

Federal law (18 U.S.C. § 922(g)) defines categories of "prohibited persons" who may not possess firearms or ammunition:

  1. Convicted felons — Any person convicted of a crime punishable by imprisonment for more than one year
  2. Fugitives from justice — Anyone with an active warrant
  3. Unlawful users of controlled substances — Including marijuana, even in states where it's legal. Federal law still classifies marijuana as a Schedule I substance, and using it makes you a prohibited person under federal firearms law.
  4. Adjudicated mentally defective — Anyone a court has determined is a danger to themselves or others, or who has been involuntarily committed to a mental institution
  5. Illegal aliens — Non-citizens who are unlawfully in the United States
  6. Dishonorably discharged veterans — Those discharged from the military under dishonorable conditions
  7. Persons who have renounced U.S. citizenship
  8. Persons under domestic violence restraining orders — Active protection orders that meet specific criteria
  9. Persons convicted of misdemeanor domestic violence — The Lautenberg Amendment (1996) prohibits firearm possession by anyone convicted of a misdemeanor crime of domestic violence
  10. Persons under felony indictment — Anyone under indictment for a felony (some states, pending federal law)

Important: These prohibitions are absolute under federal law. Even if your state restores your gun rights after a felony conviction, the federal prohibition may remain in effect unless specifically addressed.

Purchasing a Firearm

From an FFL dealer (gun shop, gun show dealer, online retailer via transfer):

  • Must be 18+ for long guns (rifles, shotguns)
  • Must be 21+ for handguns
  • Must pass a NICS background check (see our NICS guide)
  • Must complete ATF Form 4473
  • Must present valid government-issued photo ID
  • Must be a resident of the state where the FFL is located (for handguns). Long guns may be purchased in any state from an FFL.

Private sales (individual to individual):

  • Federal law does not require background checks for private sales between residents of the same state
  • However, many states have enacted "universal background check" laws that DO require checks on all transfers, including private sales
  • It is illegal to sell to anyone you know or have reason to believe is a prohibited person, even in a private sale
  • Interstate private sales MUST go through an FFL

The Gun-Free School Zones Act

Federal law (18 U.S.C. § 922(q)) makes it a felony to possess a firearm within 1,000 feet of a school. However, there are exceptions:

  • Persons with a concealed carry permit issued by the state where the school is located
  • On private property not part of school grounds
  • Firearms that are unloaded and locked in a vehicle container
  • Law enforcement officers

This law is rarely enforced on its own, but it can be added to other charges and is important for concealed carriers to understand — especially those in constitutional carry states who carry without a permit (and therefore lack the permit exemption).

NFA (National Firearms Act) Items

Certain firearms and accessories are regulated under the NFA and require additional ATF approval and a $200 tax stamp:

  • Suppressors (silencers) — Legal in 42 states with a tax stamp
  • Short-barreled rifles (SBRs) — Rifles with barrels under 16" or overall length under 26"
  • Short-barreled shotguns (SBSs) — Shotguns with barrels under 18" or overall length under 26"
  • Machine guns — Fully automatic firearms. Only pre-May 1986 registered machine guns may be owned by civilians (transferable machine guns).
  • Destructive devices — Grenades, rockets, firearms over .50 caliber bore (with some sporting exemptions)
  • Any Other Weapons (AOWs) — A catch-all category including pen guns, cane guns, and certain concealable firearms. $5 tax for transfer.

Possession of an unregistered NFA item is a federal felony. Processing time for NFA tax stamps is typically 4–12 months.

Interstate Transport

The Firearms Owners Protection Act (FOPA) provides limited protection for transporting firearms through states where they might otherwise be restricted, provided the firearms are unloaded, locked, and inaccessible during transport. See our transport guide for detailed rules.

State Law: The Variables

State gun laws vary enormously. Here are the key areas where states differ:

Concealed Carry

  • Constitutional carry states (29+) — No permit required for eligible residents. See our constitutional carry guide.
  • Shall-issue states — Must issue a permit if you meet requirements
  • May-issue states — Issuing authority has discretion (significantly limited after the 2022 Bruen decision)

Open Carry

  • Permissive — Open carry without a permit (TX, AZ, OH, GA, and many others)
  • Permit required — Open carry only with a permit (CT, some others)
  • Prohibited — Open carry banned (CA, FL, IL, NY, SC, and a few others)

Assault Weapon Bans

Several states ban or restrict certain semi-automatic firearms based on features (pistol grip, detachable magazine, threaded barrel, etc.):

  • California, New York, Connecticut, Massachusetts, New Jersey, Maryland, Hawaii, and Washington D.C.
  • These laws vary significantly in definitions and enforcement

Magazine Capacity Restrictions

Some states limit magazine capacity:

  • 10-round limit: CA, CT, MD, MA, NJ, NY, DC, and others
  • 15-round limit: CO, VT
  • No limit: Most states

Waiting Periods

Some states impose mandatory waiting periods between purchase and delivery:

  • California: 10 days
  • Florida: 3 days (handguns), waived with CWP
  • Hawaii: 14 days
  • Illinois: 72 hours (handguns), 24 hours (long guns)

Registration

Most states do not require firearm registration. Exceptions:

  • Hawaii: All firearms must be registered
  • New York City: Handguns must be registered
  • Washington D.C.: All firearms must be registered

Red Flag Laws (Extreme Risk Protection Orders)

Over 20 states have enacted red flag laws that allow courts to temporarily remove firearms from individuals deemed a danger to themselves or others. Procedures and due process protections vary by state.

Self-Defense Law

Castle Doctrine

Most states recognize the "Castle Doctrine" — the principle that you have no duty to retreat in your own home and may use deadly force against an intruder who poses an imminent threat of death or serious bodily harm.

The specifics vary:

  • Some states presume any home intruder intends to cause harm (strong Castle Doctrine)
  • Some require you to reasonably believe the intruder poses a deadly threat
  • A few states require a duty to retreat even in your own home (rare)

Stand Your Ground Laws

Over 30 states have enacted "Stand Your Ground" laws that extend the Castle Doctrine beyond the home. In these states, you have no duty to retreat before using deadly force in any place where you have a legal right to be, provided you reasonably believe deadly force is necessary to prevent imminent death or great bodily harm.

In states without Stand Your Ground laws, you generally have a duty to retreat — you must attempt to safely retreat before using deadly force (if retreat is safely possible).

Use of Force Standards

Regardless of state law, justifiable use of deadly force typically requires:

  1. Imminent threat — The threat must be happening NOW, not in the past or future
  2. Reasonable belief — A reasonable person in your situation would believe deadly force was necessary
  3. Proportional response — You can't use deadly force against a non-deadly threat
  4. Innocence — You can't claim self-defense if you initiated or escalated the confrontation

Civil Liability

Even a justified shooting may result in a civil lawsuit from the attacker or their family. Self-defense legal protection (CCW insurance) helps cover these costs. See our CCW insurance comparison.

Staying Informed

Gun laws change frequently. New legislation, court decisions, and regulatory changes can affect your rights and obligations. Stay current by:

  • Checking our state gun law guides for your state's specific rules
  • Following legislative updates from organizations like the NRA-ILA, Gun Owners of America, and the Firearms Policy Coalition
  • Taking a refresher course when you renew your concealed carry permit
  • Consulting a firearms attorney if you have specific legal questions

The Bottom Line

Knowing the law is as fundamental to responsible gun ownership as knowing the four rules of safety. Take the time to understand both the federal baseline and your state's specific requirements. When in doubt, err on the side of caution — and consult an attorney.

Explore our state gun law guides for state-specific details, and find firearms education resources at gun shows near you.