11.2 Firearms, Ballistics & Weapons Offenses (18 U.S.C. § 922/924)

11.2 Firearms, Ballistics & Weapons Offenses (18 U.S.C. § 922/924)

Quick Answer: Federal firearms prosecutions under Title 18 center on two dominant provisions: 18 U.S.C. § 922(g) (the "prohibited person / felon in possession" statute) and 18 U.S.C. § 924(c) (using, carrying, or possessing a firearm in furtherance of a drug trafficking crime or crime of violence). Section 924(c) carries non-parolable mandatory consecutive prison sentences: 5 years for basic possession in furtherance, 7 years if brandished (exhibida ostensiblemente o blandida), 10 years if discharged (disparada), and 30 years for machine guns (ametralladoras) or silencers (silenciadores). Interpreters must maintain absolute technical precision between firearm mechanisms, never confusing a magazine (cargador / proveedor) with a clip (peine), nor confounding a spent casing (casquillo percutido) with a live round (cartucho vivo) or bullet (bala / proyectil).

Firearms charges are frequently joined with drug distribution, bank robbery, violent crime, and racketeering indictments in federal court. Because weapons offenses carry severe statutory penalties and mandatory consecutive enhancements, precision in interpreting ballistics testimony, suppression hearings, and sentencing colloquies is paramount.

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1. Federal Firearms Statutory Framework: 18 U.S.C. §§ 922 & 924

Congress regulates firearms primarily through the Gun Control Act of 1968 (GCA) and the National Firearms Act (NFA), codified in Chapter 44 of Title 18 of the United States Code.

A. Prohibited Persons: 18 U.S.C. § 922(g)

Under 18 U.S.C. § 922(g), it is unlawful for any person within nine specified categories to ship or transport in interstate or foreign commerce, or possess in or affecting commerce, any firearm or ammunition, or receive any firearm or ammunition which has been shipped or transported in interstate or foreign commerce:

1. Convicted Felons [§ 922(g)(1)]: Anyone convicted in any court of a crime punishable by imprisonment for a term exceeding one year (delito mayor / delito con pena superior a un año).
2. Fugitives from Justice [§ 922(g)(2)]: Persons fleeing criminal prosecution or testimony (prófugos de la justicia).
3. Unlawful Drug Users [§ 922(g)(3)]: Anyone who is an unlawful user of or addicted to any controlled substance (consumidores ilícitos o toxicómanos de sustancias controladas).
4. Adjudicated Mentally Defective [§ 922(g)(4)]: Persons adjudicated as a mental defective or committed to a mental institution (personas declaradas con incapacidad mental o internadas en institución psiquiátrica).
5. Undocumented / Illegal Aliens [§ 922(g)(5)]: Noncitizens unlawfully present in the United States or admitted under nonimmigrant visas (extranjeros en situación irregular).
6. Dishonorable Discharge [§ 922(g)(6)]: Individuals discharged from the Armed Forces under dishonorable conditions (dados de baja de las fuerzas armadas bajo condiciones deshonrosas).
7. Renounced Citizens [§ 922(g)(7)]: Persons who have formally renounced U.S. citizenship (personas que han renunciado a la ciudadanía estadounidense).
8. Domestic Violence Restraining Orders [§ 922(g)(8)]: Persons subject to court orders restraining them from harassing, stalking, or threatening an intimate partner or child (órdenes de alejamiento o protección por violencia doméstica).
9. Misdemeanor Domestic Violence Convictions [§ 922(g)(9)]: Anyone convicted of a misdemeanor crime of domestic violence (delito menor de violencia doméstica).

Landmark Scienter Requirement (Rehaif v. United States): In Rehaif v. United States, 139 S. Ct. 2191 (2019), the Supreme Court held that in prosecutions under § 922(g) and § 924(a)(2), the government must prove not only that the defendant knowingly possessed a firearm, but also that they knew they had the relevant status (e.g., knew they had been convicted of a felony or were unlawfully in the country) at the time of possession. This requires interpreters to render nuanced mental state (mens rea) jury instructions with absolute fidelity.

B. Firearm in Furtherance of a Crime: 18 U.S.C. § 924(c)

Under 18 U.S.C. § 924(c)(1)(A), any person who, during and in relation to any crime of violence or drug trafficking crime, uses or carries a firearm, or who, in furtherance of any such crime, possesses a firearm, faces severe mandatory consecutive sentences that cannot run concurrently (no pueden cumplirse de forma concurrente o simultánea) with any other sentence:

+-----------------------------------------------------------------------------------+
|              18 U.S.C. § 924(c) MANDATORY CONSECUTIVE PENALTY LADDER              |
|                                                                                   |
|  Possession in Furtherance   -->  5 Years Consecutive (Mínimo obligatorio 5 años)|
|              |                                                                    |
|  Brandished                  -->  7 Years Consecutive (Blandida / Exhibida 7 años)|
|              |                                                                    |
|  Discharged                  --> 10 Years Consecutive (Disparada 10 años)         |
|              |                                                                    |
|  Short-barreled Rifle/Shotgun--> 10 Years Consecutive (Cañón recortado 10 años)   |
|              |                                                                    |
|  Machine Gun / Silencer      --> 30 Years Consecutive (Ametralladora 30 años)     |
|              |                                                                    |
|  Second / Subsequent § 924(c)--> 25 Years Consecutive (Reincidencia 25 años)      |
+-----------------------------------------------------------------------------------+

• Brandish (Blandir / Exhibir ostensiblemente): Defined by statute as displaying all or part of the firearm, or otherwise making the presence of the firearm known to another person, in order to intimidate that person (para intimidar o coaccionar), regardless of whether the weapon was pointed directly at anyone.
• Discharge (Disparar / Accionar): The actual mechanical discharging of a projectile.
• First Step Act of 2018 Clarification: Prior to 2018, federal prosecutors could "stack" multiple § 924(c) counts in a single indictment (e.g., two counts in one robbery yielded 5 + 25 = 30 years). The First Step Act clarified that the 25-year enhancement for a second or subsequent conviction applies only after a prior § 924(c) conviction has become final in a prior proceeding.

C. Straw Purchasing & Obliterated Serial Numbers

• Straw Purchase (Compra simulada / Compra por persona interpuesta o testaferro): Under 18 U.S.C. § 922(a)(6) and 18 U.S.C. § 932 (enacted under the Bipartisan Safer Communities Act of 2022), it is a federal crime to purchase a firearm on behalf of an unauthorized third party by making false statements on ATF Form 4473 (Formulario 4473 de la Oficina de Alcohol, Tabaco, Armas de Fuego y Explosivos).
• Obliterated Serial Number (Número de serie borrado, limado, alterado o desfigurado): Under 18 U.S.C. § 922(k), it is unlawful to possess, transport, or receive any firearm that has had the manufacturer's serial number removed, altered, or obliterated.
• Ghost Guns (Armas fantasma / Armas de fuego no serializadas): Homemade or privately manufactured firearms (PMFs) assembled from polymer receiver blanks (e.g., "80% lower receivers") or 3D-printed parts lacking commercial serial numbers.

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2. Firearm Anatomy, Classifications & Mechanical Distinctions

Courtroom testimony by ATF special agents, firearms examiners, and arresting officers requires interpreters to command precise terminology across major firearm categories:

A. Major Firearm Categories

1. Handgun (Arma corta): Designed to be fired with one or both hands.
   • Revolver (Revólver): Features a revolving cylinder (tambor giratorio) containing multiple chambers (recámaras). Single-action (acción simple—hammer must be cocked manually before pulling the trigger) vs. Double-action (doble acción—trigger pull cocks and releases the hammer in one continuous motion).
   • Semi-Automatic Pistol (Pistola semiautomática): Uses energy from the fired cartridge to cycle the slide (corredera), extract and eject the spent casing, cock the firing mechanism, and load a new cartridge from a spring-loaded detachable magazine (cargador extraíble).
2. Long Gun (Arma larga): Designed to be braced against the shoulder.
   • Rifle (Fusil / Rifle): Shoulder-fired weapon with a rifled barrel designed to impart spin to a single projectile. Actions include bolt action (cerrojo), lever action (palanca), and semi-automatic (semiautomático).
   • Shotgun (Escopeta): Smoothbore weapon (ánima lisa) firing a shell (cartucho de escopeta) loaded with pellets/shot (perdigones / postas) or a single solid slug (bala de escopeta / breneke). Actions include pump action / slide action (corredera / trombón) and break action (basculante).
   • Sawed-Off / Short-Barreled Shotgun (Escopeta de cañón recortado): Shotgun with a barrel length under 18 inches or an overall length under 26 inches, strictly regulated under the NFA.
3. Machine Gun / Automatic Firearm (Ametralladora / Fusil automático): Any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger (26 U.S.C. § 5845(b)).
   • Auto-Sear / Glock Switch (Interruptor de conversión automática / Selector de tiro): An illegal aftermarket device inserted into the rear of a semi-automatic handgun slide that converts it into a fully automatic machine gun capable of firing 1,200 rounds per minute.

B. Critical Mechanical Distinction: Magazine vs. Clip (Cargador vs. Peine)

One of the most persistent errors committed by untrained interpreters on the FCICE is confusing a magazine with a clip:

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3. Forensic Ballistics, Cartridge Anatomy & Expert Testimony

When a shooting incident is prosecuted in federal court, firearms examiners from the FBI Laboratory or ATF Forensic Science Laboratory deliver expert testimony under Federal Rule of Evidence 702. Interpreters must translate every anatomical and chemical term without hesitation.

A. Anatomy of a Live Cartridge (Anatomía de un Cartucho Vivo)

A single unit of modern ammunition is a cartridge (cartucho) or round (tiro / cartucho vivo). It comprises four distinct components:

1. Bullet / Projectile (Bala / Proyectil / Ojiva): The metal projectile (lead, copper-jacketed, or alloy) seated in the case mouth that is propelled through the barrel upon firing.
2. Cartridge Case / Casing (Casquillo / Vaina / Casquillejo): The brass, steel, or polymer container that houses the propellant powder, holds the primer in its base, and secures the projectile in its mouth. Once fired and ejected, it is referred to as a spent casing (casquillo percutido o servido).
3. Gunpowder / Propellant (Pólvora / Carga de proyección): Smokeless powder (pólvora sin humo) that burns rapidly (deflagrates) to generate high-pressure gas that propels the bullet down the barrel.
4. Primer (Cebador / Fulminante / Cápsula iniciadora): A small metal cup at the base of the casing containing shock-sensitive explosive compounds (lead styphnate, barium nitrate, antimony sulfide). When struck by the firing pin, it ignites the gunpowder charge.

B. Firearm Mechanical Action & Toolmark Identification

When the trigger (gatillo / disparador) is pulled, the mechanical firing sequence occurs:

1. The hammer (martillo) or striker (percutor lanzado) drives the firing pin (aguja percutora / percutor) forward into the primer cup.
2. The expanding gases expand the brass casing, sealing it against the walls of the chamber (recámara).
3. The projectile is forced into the barrel (cañón), where the helical spiral grooves—rifling (rayado o estriado helicoidal)—impart gyroscopic spin for aerodynamic stability.
   • Lands (Tierras): The raised metal ridges inside the rifled bore.
   • Grooves (Estrías): The recessed spiral channels cut into the bore.
4. As the bullet travels down the bore, the lands and grooves carve microscopic striations—toolmarks (marcas de estriado / huellas de percusión)—into the bullet surface.
5. The extractor (uña extractora) hooks the casing rim (reborde), pulling it from the chamber, and the ejector (expulsor / eyector) kicks the spent casing through the ejection port (ventana de expulsión).
6. A ballistics examiner uses a comparison microscope (microscopio de comparación balística) to match microscopic striations on evidence projectiles and firing pin indentations on spent casings against test-fired standards (disparos de prueba) from a seized firearm.

C. Gunshot Residue (GSR) (Residuos de Disparo / Deflagración)

When a firearm discharges, vaporized propellant and primer residue blow back onto the shooter's hands, sleeves, and surrounding surfaces. Scanning Electron Microscopy / Energy Dispersive X-Ray Spectroscopy (SEM/EDS) tests for three signature heavy metals: Lead (Plomo), Barium (Bario), and Antimony (Antimonio).

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4. Bilingual Firearms & Ballistics Terminology Table (35 Terms)

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5. Ballistics Firing Cycle & Sentencing Escalation Diagram

The following diagram models the mechanical firing sequence, toolmark evidence generation, and corresponding federal sentencing implications under 18 U.S.C. § 924(c):