US Federal 2025-2026 Regular Session

US Federal House Bill HB4257

Introduced
 
Introduced
6/30/25  

Caption

End Domestic Terrorism Act

Summary

HB4257, titled the End Domestic Terrorism Act, would create a new federal offense for mass killings involving a machinegun, a destructive device, or a defined “covered semiautomatic weapon” when the crime occurs in or affects interstate or foreign commerce and takes place at certain sensitive or public locations. The bill sets the penalty at imprisonment for any term of years or life if the offender kills three or more people in a single incident. It also expands the federal material-support statute to cover this new offense. The bill defines “covered semiautomatic weapon” broadly to include certain semiautomatic rifles and shotguns with specified features, AK- and AR-type weapons and variants, and rate-of-fire accelerating devices that do not convert a firearm into a machinegun. It also requires the Attorney General to issue annual reports to Congress on cases charged under the new offense and related material-support charges, including demographic information about defendants and details about the offense. In addition, it requires a public DOJ report within 180 days of charges being filed, covering the number of people present, government response costs, lost business revenue, and victim-assistance payments.

Impact

If enacted, the bill would add a new section to chapter 113B of title 18 of the U.S. Code, creating a federal mass-killing offense tied to the use of specified firearms and devices. It would also amend the definition section for terrorism-related offenses, update the material-support statute to include the new offense, and require new reporting obligations in federal criminal justice records and DOJ public reporting. The bill would affect federal prosecutors, the Department of Justice, victims and businesses impacted by mass shootings, and owners or users of the firearms and accessories covered by the definition.

Sentiment

The bill’s framing and title indicate a strong public-safety and anti-mass-shooting intent, and the text suggests a punitive approach aimed at deterring or addressing high-casualty attacks. However, no committee transcript or vote history is available here, so there is no recorded legislative debate or roll-call sentiment to assess. Based on the bill text alone, the overall posture is aggressive and security-focused rather than compromise-oriented.

Contention

The main likely points of contention are the breadth of the firearm definition and the scope of federal criminal liability. The bill covers a wide range of semiautomatic rifles and shotguns, AK/AR-type weapons, and rate-of-fire accessories, which could draw objections from gun-rights advocates and those concerned about overbreadth or vagueness. The reporting provisions requiring demographic data on defendants and detailed public cost reporting may also raise privacy, fairness, and administrative burden concerns. Supporters are likely to emphasize mass-casualty prevention, enhanced penalties, and transparency about the costs of such crimes.

Companion Bills

No companion bills found.

Previously Filed As

US H0184

Amends existing law to provide for the crime of domestic terrorism.

US H0285

Amends existing law to provide for the crime of domestic terrorism.

US HR26

Deeming certain conduct of members of Antifa as domestic terrorism and designating Antifa as a domestic terrorist organization.

US SB2457

Domestic Terrorism Prevention Act of 2025

US SR45

Urges Federal Bureau of Investigation to categorize white supremacists as domestic terrorists.

US AR106

Urges Federal Bureau of Investigation to categorize white supremacists as domestic terrorists.

US HB4787

The Anti-Terrorism Act

US HB2757

Relating to the Anti-Terrorism Act

US S1714

No Tax Dollars for Terrorists Act

US H4009

No Tax Dollars for Terrorists Act

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