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Defacing a Firearm

Facing an accusation of defacing a firearm in Colorado may not sound as serious as violent crimes, but the charge carries significant consequences. Defacing or possessing a defaced firearm is a felony offense under Colorado law, and a conviction can result in prison time, steep fines, and a permanent criminal record that impacts your future rights, including the right to possess firearms.

Defacing a Firearm Attorney in Colorado

Unlike other weapons-related crimes, defacing a firearm centers on the firearm’s identification. The law is designed to prevent people from hiding the origin of a weapon by altering or removing its serial number. Because this offense is often connected to other criminal allegations, prosecutors treat it harshly. Having the right defense attorney is critical to protecting your rights and freedom.

If you have been charged with Defacing a firearm in Colorado, then you need a strong criminal defense attorney. The Law Office of Matthew Martin is prepared to provide full-service legal representation for clients accused of weapon crimes and firearm related offenses.

Call the Law Office of Matthew A. Martin, P.C. at (303) 725-0017 to schedule your free consultation today.

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Colorado Laws on Defacing a Firearm

Under C.R.S. § 18-12-104, it is unlawful for any person to:

  • Deface a Firearm: Knowingly remove, alter, or obliterate the manufacturer’s serial number on a firearm.
  • Possess a Defaced Firearm: Knowingly possess a firearm with its serial number removed, altered, or obliterated.

This law is meant to ensure traceability of firearms for law enforcement and prevent the circulation of untraceable or “ghost” guns.

Importantly, prosecutors must prove the accused acted knowingly, meaning the person either defaced the weapon themselves or was aware that the firearm was defaced when they possessed it.

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Conduct That Constitutes Defacing a Firearm

Colorado law under C.R.S. § 18-12-104 makes it a crime to knowingly remove, alter, or obliterate a firearm’s serial number, or to knowingly possess a firearm that has already been defaced. The law focuses on the weapon’s traceability, and many different actions may be treated as “defacing” a firearm.

Examples of Prohibited Conduct

  • Removing or Grinding Off Serial Numbers
     Using tools such as grinders, files, or sandpaper to scratch away or erase the identifying number on a firearm.
  • Altering or Covering Serial Numbers
     Modifying a firearm so the serial number is disguised, altered, or hidden under paint, tape, or plating.
  • Stamping Over or Restamping
     Replacing or stamping a new number on the firearm in a way that conceals the original serial number.
  • Chemical Defacement
     Using solvents, acid, or other chemicals to corrode or remove the serial number.
  • Possessing a Defaced Firearm
     Even if the accused did not personally alter the firearm, knowingly possessing a weapon with an illegible or missing serial number also constitutes an offense.

Important Considerations

  • Intent Matters — The prosecution must prove the defendant acted knowingly. Accidentally damaging a serial number through wear, rust, or repairs does not automatically equal criminal conduct.
  • Partial Defacement — Even if the serial number is only partially removed, obscured, or altered, the firearm may be considered defaced under the law.
  • Constructive Possession — You can be charged even if the firearm was not on your person, so long as prosecutors claim you had control over it (e.g., in your car or home).

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Common Misunderstandings About Defacing a Firearm

Not every firearm with a damaged or hard-to-read serial number has been “defaced” under Colorado law. Many guns, particularly older or heavily used ones, show natural signs of wear and tear that can lead to misunderstandings. Prosecutors still have to prove the damage was caused knowingly and intentionally before a conviction can occur.

Situations That Often Cause Confusion

  • Normal Wear and Tear
     Over years of use, handling, holstering, and cleaning, the engraved serial number may become faint or partially worn away.
  • Rust and Corrosion
     Firearms exposed to moisture or poor storage conditions often develop rust, which can obscure or damage markings without any criminal intent.
  • Accidental Damage from Repairs
     Gunsmithing, refinishing, or home repair efforts (such as sanding, bluing, or re-coating) can unintentionally scratch or cover a serial number.
  • Manufacturing Defects or Poor Stamping
     Some older firearms, imported models, or cheaply manufactured weapons may have faint or shallow serial numbers that were never clear in the first place.
  • Cosmetic Modifications
     Custom paint jobs, coatings, or plating may unintentionally cover or blur a serial number, even though the intent was aesthetic rather than criminal.

The difference between innocent damage and criminal defacement often lies in proving intent. A defense attorney can highlight these distinctions to show that a firearm’s condition is the result of natural causes or legitimate maintenance, not deliberate attempts to hide the weapon’s identity.

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Key Elements Considered by a Jury

When hearing a case of defacing a firearm, a Colorado jury will examine several factors:

  • Condition of the Serial Number — Was the number removed, altered, or rendered illegible?
  • Defendant’s Knowledge — Did the accused knowingly deface the firearm, or knowingly possess one that had already been defaced?
  • Possession and Control — Was the firearm in the defendant’s possession or control at the time of arrest?
  • Intent to Conceal or Commit Other Crimes — Although intent to use the weapon in another crime is not required for conviction, prosecutors often argue it as a factor.

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Penalties and Aggravating Factors

Basic Penalties

Defacing or possessing a defaced firearm in Colorado is a Class 1 Misdemeanor:

  • Jail: Up to 364 days in county jail
  • Fines: Up to $1,000
  • Criminal Record: A conviction results in a permanent criminal record that can affect employment, housing, and firearm ownership.

Aggravating Factors

While the statute itself classifies the crime as a misdemeanor, aggravating circumstances can increase the severity of the case or lead to additional charges:

  • Firearm Used in Commission of a Felony — If the defaced firearm is tied to another crime, penalties may be compounded.
  • Repeat Offenses — Prior weapons convictions may influence sentencing.
  • Federal Charges — In some cases, defacing or possessing a defaced firearm may trigger federal prosecution, with harsher penalties.

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Defenses to Defacing a Firearm Charges in Colorado

Defacing a firearm is a serious charge, but like many weapons-related offenses, the prosecution must prove every element of the crime beyond a reasonable doubt. An experienced defense attorney can raise several strategies to challenge the state’s case.

Lack of Knowledge

The law requires proof that the defendant acted knowingly. If a firearm was purchased secondhand, inherited, or acquired without awareness that its serial number was altered or missing, the accused may not have had the intent necessary for conviction.

No Defacement Proven

Not all damaged serial numbers are the result of intentional defacement. Serial numbers can become unreadable for reasons unrelated to criminal conduct. If the defense can demonstrate that the condition of the firearm is due to natural deterioration or accidental damage, rather than deliberate action, the prosecution’s case may fail.

No Possession or Control

Prosecutors must prove the accused had possession or control of the firearm. If the gun was discovered in a shared space (such as a car or home), establishing exclusive possession can be difficult.

Unlawful Search and Seizure

If the firearm was found through an illegal traffic stop, improper warrant, or unconstitutional search, the defense may move to suppress that evidence under the Fourth Amendment. Without the firearm, the state cannot pursue charges.

Mistaken Identity or False Allegations

In some cases, a firearm may have passed through multiple hands. The defense can argue that the accused was wrongly identified as the person who defaced or knowingly possessed the weapon.

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Role of a Denver Firearm Defense Attorney

A defense attorney experienced in weapons crimes will:

  • Examine the Evidence — Investigating the firearm itself, forensic tests, and police reports.
  • Challenge Possession and Knowledge — Questioning whether prosecutors can prove the defendant knowingly possessed a defaced firearm.
  • File Constitutional Motions — Suppressing evidence obtained through illegal searches or improper procedures.
  • Mitigate Consequences — Negotiating for dismissal, reduction of charges, or alternatives to incarceration.
  • Guide the Client — Explaining the legal process clearly and providing support throughout the case.

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Frequently Asked Questions

What does it mean to deface a firearm?
 Defacing a firearm means knowingly removing, altering, or obliterating the manufacturer’s serial number, or knowingly possessing a firearm that has been defaced.

Is defacing a firearm a felony in Colorado?
 No. Under state law, defacing or possessing a defaced firearm is a Class 1 misdemeanor. However, related charges or federal prosecution can increase penalties.

Can I go to jail for defacing a firearm?
 Yes. A conviction carries up to 364 days in county jail.

What if I bought the gun already defaced?
 If you did not know the firearm was defaced, lack of knowledge may be a defense. Prosecutors must prove you acted knowingly.

Can federal charges apply?
 Yes. In certain cases, especially involving interstate commerce or trafficking, federal law may apply with harsher penalties.

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Resources

Colorado Revised Statutes § 18-12-104 – Defacing Firearm – Full statutory text outlining defacing and possessing a defaced firearm in Colorado.

Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) – Federal resource explaining firearm laws, serial number requirements, and related federal penalties.

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Hire a Firearm Defense Attorney in Denver, Colorado

If you have been accused of defacing a firearm or possessing a defaced weapon, you need a skilled criminal defense attorney to protect your rights. Call (303) 725-0017 today for a free consultation with the Law Office of Matthew A. Martin, P.C.

We represent clients throughout the Denver metro area, including Jefferson, Douglas, Arapahoe, Broomfield, Adams, and Boulder counties.