Under federal law, domestic terrorism is defined but not directly charged. No federal statute makes “domestic terrorism” itself a crime, so a person who carries out a politically motivated attack inside the United States is prosecuted under existing criminal statutes — explosives, firearms, weapons of mass destruction, material support — and then faces a sentencing enhancement that pushes the prison term into terrorism territory.1Congressional Research Service. Understanding and Conceptualizing Domestic Terrorism: Issues for Congress That split between definition and charge shapes every stage of a federal domestic terrorism case.
How the Statute Defines Domestic Terrorism
Under 18 U.S.C. § 2331(5), conduct qualifies as domestic terrorism only when three things are true at once. The act must be dangerous to human life and violate federal or state criminal law. It must appear intended to intimidate a civilian population, coerce a government policy change, or disrupt government operations through mass destruction, assassination, or kidnapping. And it must take place primarily within U.S. territory.2Office of the Law Revision Counsel. 18 USC 2331 – Definitions
The intent prong is what separates terrorism from ordinary violent crime. A mass shooting driven by a personal grudge does not meet the definition, no matter how many people are hurt. The violence has to carry a political or ideological purpose visible enough that investigators can point to communications, writings, or affiliations showing the goal was to intimidate a population or pressure the government. Without that evidence, the same conduct is prosecuted as murder, arson, or assault, with no terrorism label attached.
Geography matters too. If the actors or objectives cross international borders, the case moves under the separate international terrorism definition in § 2331(1), which opens a different set of investigative and prosecution tools.
Why There Is No Standalone Domestic Terrorism Charge
This is the counterintuitive core of the framework. Federal law defines domestic terrorism, tracks it, and uses it to enhance sentences, but there is no crime called domestic terrorism that a prosecutor can list on an indictment. Someone who bombs a federal building is charged with using an explosive, not with domestic terrorism.1Congressional Research Service. Understanding and Conceptualizing Domestic Terrorism: Issues for Congress
The contrast with international terrorism is sharp. Under 18 U.S.C. § 2339B, anyone who provides material support to a designated foreign terrorist organization faces up to 20 years, or life if someone dies.3Office of the Law Revision Counsel. 18 USC 2339B – Providing Material Support or Resources to Designated Foreign Terrorist Organizations That statute lets prosecutors charge someone who sends money or travels to join a listed group before any attack happens. No parallel mechanism exists on the domestic side. The government maintains no list of designated domestic terrorist organizations, and no federal law criminalizes providing support to one. The Domestic Terrorism Prevention Act was reintroduced in 2025, but as of early 2026 it has not been enacted.
The Charges Prosecutors Actually Use
Because the terrorism label itself does not travel on the indictment, the charges in these cases depend on what the defendant did.
Explosives Offenses
Under 18 U.S.C. § 844(i), using fire or explosives to destroy property connected to interstate commerce carries 5 to 20 years. The range rises to 7 to 40 years if anyone is injured, and reaches any term of years, life, or the death penalty if anyone dies.4Office of the Law Revision Counsel. 18 USC 844 – Penalties The statute reaches the conduct regardless of whether it is also labeled terrorism.
Weapons of Mass Destruction
The federal definition of “weapon of mass destruction” is broader than the phrase suggests. Under 18 U.S.C. § 2332a, it covers any destructive device as defined in federal firearms law, including pipe bombs and grenades, along with chemical, biological, and radiological weapons.5Office of the Law Revision Counsel. 18 USC 2332a – Use of Weapons of Mass Destruction Using or attempting to use one against people or property inside the United States carries any term of years or life, with the death penalty available if someone dies.
Stacked Firearms Charges
Under 18 U.S.C. § 924(c), a firearm used during a violent crime adds a consecutive mandatory minimum on top of the underlying sentence. Possession adds at least 5 years. Brandishing raises the floor to 7, and firing it to 10. For machineguns and destructive devices, the mandatory minimum is 30 years.6Office of the Law Revision Counsel. 18 USC 924 – Penalties Stacking these consecutive terms on top of the underlying crime is how prosecutors assemble decades-long sentences without ever charging terrorism as such.
Material Support Under § 2339A
Separate from the foreign-organization statute, 18 U.S.C. § 2339A criminalizes providing material support when the provider knows or intends that the resources will be used to carry out certain federal crimes. It does not require a designated organization. It reaches anyone who furnishes money, weapons, lodging, training, false identification, transportation, or other tangible or intangible resources in preparation for or in furtherance of specific violent federal offenses.7Office of the Law Revision Counsel. 18 USC 2339A – Providing Material Support to Terrorists The maximum is 15 years, or life if someone dies.
The Terrorism Sentencing Enhancement
The mechanism that puts terrorism-level punishment on top of ordinary charges is U.S. Sentencing Guidelines § 3A1.4. When a court finds that a felony involved or was intended to promote a federal crime of terrorism, the defendant’s offense level jumps by 12 levels, with a floor of level 32. The defendant is also placed automatically in Criminal History Category VI, the most serious category, regardless of any prior record.8United States Sentencing Commission. USSG 3A1.4 – Terrorism
The practical effect is enormous. A first-time offender who would otherwise face around 10 years can land at 20 or more once both adjustments apply. Treating someone with no prior record as a career offender for sentencing purposes is what gives the enhancement its weight. This is how the federal system imposes terrorism-level punishment through a definition and a sentencing rule rather than a standalone crime.
To trigger it, the offense must qualify as a “federal crime of terrorism” under 18 U.S.C. § 2332b(g)(5). That provision has its own two-part test: the offense must be calculated to influence government conduct through intimidation or coercion, or to retaliate against the government, and it must violate one of roughly 50 listed federal statutes covering everything from destruction of aircraft to attacks on mass transportation systems.9Office of the Law Revision Counsel. 18 USC 2332b – Acts of Terrorism Transcending National Boundaries
Forfeiture, Restitution, and a Civil Remedy Gap
Beyond prison, the government can seize property connected to terrorism. Under 18 U.S.C. § 981, all assets of anyone who planned or carried out a federal crime of terrorism are subject to civil forfeiture, as are assets acquired or maintained to support terrorism and property derived from or used in a terrorist act.10Office of the Law Revision Counsel. 18 USC 981 – Civil Forfeiture The authority reaches overseas property if the government shows an act in furtherance occurred within U.S. jurisdiction.
Restitution is mandatory when a terrorism case produces a conviction for a crime of violence. Under 18 U.S.C. § 3663A, defendants must pay for victims’ medical treatment, rehabilitation, lost income, funeral expenses if the victim died, and costs like child care and transportation tied to the prosecution.11Office of the Law Revision Counsel. 18 USC 3663A – Mandatory Restitution to Victims of Certain Crimes For damaged property, defendants must return it or pay full replacement value.
One remedy does not reach domestic victims. The treble-damages civil action under 18 U.S.C. § 2333 is limited to injuries caused by acts of international terrorism.12Office of the Law Revision Counsel. 18 USC 2333 – Civil Remedies Victims of domestic attacks can still bring state tort claims, but the federal treble-damages route is closed to them.
Investigation Tools and Their Domestic Limits
The FBI runs domestic terrorism investigations through roughly 200 Joint Terrorism Task Forces, which combine FBI agents with investigators from state, local, and other federal agencies to share intelligence and disrupt plots before they happen.13Federal Bureau of Investigation. Joint Terrorism Task Forces The emphasis is on prevention, with the criminal case built from whatever evidence the investigation produces.
Some of the government’s strongest investigative tools stop at the domestic line. National Security Letters under 18 U.S.C. § 2709 let the FBI compel phone records and subscriber information without a traditional warrant, but the statute authorizes them only for investigations related to international terrorism or foreign intelligence, not purely domestic cases.14Office of the Law Revision Counsel. 18 USC 2709 – Counterintelligence Access to Telephone Toll and Transactional Records Domestic investigators have to use grand jury subpoenas and court-authorized wiretaps instead.
Delayed-notice search warrants are available in terrorism cases. Under 18 U.S.C. § 3103a, a court can authorize a search without immediate notice to the occupant if it finds reasonable cause to believe that immediate notice would produce an adverse result such as destruction of evidence or flight. Notice must be given within 30 days, with extensions of up to 90 days available on a showing of good cause.15Office of the Law Revision Counsel. 18 USC 3103a – Additional Grounds for Issuing Warrant
Constitutional Limits on Prosecution
The First Amendment draws a hard line between speech and criminal conduct. Under Brandenburg v. Ohio, the government cannot punish advocacy of violence unless the speech is directed at producing imminent lawless action and is likely to actually produce it. Abstract arguments about the moral justification for political violence remain protected, however alarming they sound. Someone posting online about the theoretical necessity of armed resistance is exercising a constitutional right; someone posting detailed instructions for a specific attack next Tuesday is not. Investigators can monitor escalating rhetoric, but speech alone is not a crime. The case has to identify concrete steps toward carrying out an attack before charges become viable.
The entrapment defense comes up often because domestic terrorism investigations are frequently proactive, with undercover agents or informants offering resources and encouragement. The defendant has to show two things: that the government induced the criminal conduct, and that the defendant was not already predisposed to commit it.16U.S. Department of Justice. Criminal Resource Manual 645 – Entrapment Elements Simply offering an opportunity is not inducement. The defendant has to show something closer to persuasion, pressure, or extraordinary promises. And even where inducement is shown, the defense fails if the government can prove predisposition, which courts often find in how quickly and eagerly the defendant went along with the plan. The defense rarely succeeds in terrorism cases because the government typically introduces extensive evidence of the defendant’s own statements and preparations.
State Terrorism Laws
More than 30 states and Washington, D.C. have enacted their own criminal terrorism statutes, which can fill some of the gap left by the absence of a standalone federal charge. State maximums range from 15 years to life, depending on the jurisdiction and whether anyone died. Some states focus narrowly on specific conduct like threatening mass violence; others track the federal definition closely.
State and federal charges can proceed in parallel from the same conduct without triggering double jeopardy, because state and federal governments are treated as separate sovereigns. A defendant can face state terrorism charges alongside federal explosives or firearms charges, each with its own theory and its own range of punishment.