Law360 (August 4, 2026, 10:46 PM EDT) -- The U.S. Department of Justice pushed back against Connecticut's bid to toss the federal government's legal challenge to a state law subjecting in-custody deaths to state oversight, requiring federal agents to wear identifying badges, and banning law enforcement officers from wearing facemasks, calling the act "blatantly unconstitutional."

In its opposition filed Monday, the federal government asks the court to deny Connecticut's motion to dismiss the lawsuit it filed in May. The filing in Connecticut federal court argues that the state law, S.B. 397, is unlawful because it attempts to regulate federal officers while they perform their official duties and exposes them to state criminal penalties for noncompliance.

"This is blatantly unconstitutional," the opposition filing states.

The federal government contends that these provisions violate the longstanding principle that states cannot regulate federal operations.

The federal government points to an April decision by a Ninth Circuit panel that temporarily blocked California from enforcing part of a law requiring law enforcement officers — including federal immigration agents — to visibly display identification, ruling it is likely unconstitutional.

The federal government's lawsuit challenges four provisions of the Connecticut law, which imposes the state's use-of-force standards on federal officers and regulates what they may wear, including restrictions on facial coverings and requirements for personal identification.

Connecticut moved to dismiss the United States' complaint for lack of subject matter jurisdiction, citing standing and prudential ripeness concerns.

In its Monday filing, the United States argues that it has standing because the law will run afoul of the federal government's sovereign immunity, thus posing cognizable harm to the United States.

That's because "federal officers intend to engage in conduct restricted by the statute, and there is a credible threat of enforcement," states the United States' opposition to Connecticut's motion to dismiss.

In its motion to dismiss, the state said the federal government also lacked standing to challenge the state law's face covering and visible identification requirements because the complaint does not name a proper defendant. Connecticut's governor, attorney general and chief state's attorney do not enforce the requirements, but instead individual state's attorneys do, the state said.

That standard relates to the Supreme Court's 1908 decision in Ex Parte Young, which involves an exception to state sovereign immunity under the Eleventh Amendment, the federal government tells the court.

The federal government, however, "is not subject to the Eleventh Amendment and may sue a state," the opposition filing states.

The Eleventh Amendment only protects state governments from being sued in federal court by people from other states or foreign countries, the federal government argues.

Governor Ned Lamont is also a proper party to the action because he is vested through state law with the authority to take action concerning matters involving law enforcement and the protection of the state's citizens, the federal government says.

"Moreover, Governor Lamont has indicated an intent to enforce SB 397 against federal officers and agents," the federal government states in its Monday filing.

Attorney General William Tong is also a proper party to the litigation, since he has "general supervision" over legal matters in which the state is an interested party and similarly expressed an intent to enforce SB 397 against the federal government, the federal government underscores.

Finally, the legal challenge to the constitutionality of SB 397 is ripe for review, the federal government argues.

Connecticut claims that the United States is jumping the gun by seeking a preemptive ban on its law, the federal government notes. But the Supreme Court has found that seeking relief from threatened action does "not require a plaintiff to expose himself to liability before bringing suit to challenge the basis for the threat—for example, the constitutionality of a law threatened to be enforced," citing the High Court's 2007 decision in MedImmune, Inc. v. Genentech, Inc.

In its July motion to dismiss, the state argues that it has a longstanding right to prosecute those who violate its criminal laws, including federal officials.

"Taken to its logical conclusion, the United States' position would mean federal agents could commit crimes and violate Connecticut residents' rights with impunity, accountable to no one," Connecticut said.

The state also argues that the face covering and visible identification requirements of Senate Bill 397 impose "incidental burdens" on federal operations at most, stressing those statutes' numerous exceptions, such as for undercover operations.

The Ninth Circuit's recent decision to grant a preliminary injunction over a similar law enforcement identification law in California is not persuasive, Connecticut argues.

While a prong of intergovernmental immunity prohibits certain direct regulations of the federal government, it does not bar "all state regulation which may touch the activities of the federal government," the motion to dismiss states, citing the U.S. Supreme Court's 1976 decision in Hancock v. Train .

Nor does it provide federal officers with immunity from following state law while acting in the course of their employment, Connecticut says, pointing to the U.S. Supreme Court's landmark 1920 intergovernmental immunity decision in Johnson v. Maryland.

In that case, the High Court said federal employees acting in their official capacities are still subject to general local rules that might incidentally affect the mode of carrying out the employment.

The key question is whether the law "seeks to improperly 'control' the employee's federal duties, or whether the law only 'might affect incidentally the mode of carrying out the employment," the state says, citing Johnson.

Representatives for the parties did not immediately respond to a request for comment Tuesday.

The federal government is represented by Brett A. Shumate, Yaakov M. Roth, Alessandra Faso and Alexandra McTague Schulte of the U.S. Department of Justice.

The Connecticut defendants are represented by Janelle Medeiros, Timothy Holzman and Edward Rowley of the Connecticut Office of the Attorney General.

The case is U.S. v. State of Connecticut et al., case number 3:26-cv-00758, in the U.S. District Court for the District of Connecticut.

--Additional reporting by Ganesh Setty, Aaron Keller and Tom Lotshaw. Editing by Vaqas Asghar.

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