Courts Split on Role IRS Can Play in Immigration Enforcement, Data Sharing

In the span of two days, courts have issued somewhat conflicting rulings about what the Internal Revenue Service can do to assist the Trump administration’s immigration enforcement efforts.

On Thursday, U.S. District Judge Colleen Kollar-Kotelly for the District of Columbia determined that almost 43,000 addresses the IRS shared with Immigration and Customs Enforcement last August were provided without confirmation of a valid address.

Two days earlier, in a separate case, the U.S. Court of Appeals for the District of Columbia gave a green light for the Internal Revenue Service to share information about illegal aliens with the Department of Homeland Security.

The D.C. Circuit upheld a lower court decision rejecting a temporary injunction on the IRS’ actions until the case is completed. The court also said the plaintiffs “are unlikely to succeed on the merits of their claims.” In the case led by Centro de Trabajadores Unidos, an immigrants’ rights group sued the Treasury Department last March over the information sharing.

The IRS shared taxpayer identification numbers and address information with the Department of Homeland Security to assist in finding illegal aliens in the country. The IRS assigns taxpayer identification numbers to individuals who lack Social Security numbers, usually noncitizens, so those individuals can file taxes.

Both cases focus on IRS data sharing. However, the D.C. Circuit ruled that a federal statute allows for sharing data with other federal agencies. By contrast, the district court ruling focused on whether the IRS followed proper procedures in sharing the data.

“The statute straightforwardly says that addresses can be disclosed if they are not ‘taxpayer return information,’” the court opinion says. It adds, “Addresses are thus not ‘taxpayer return information,’ so they do not receive any special protection from disclosure.”

The case in the district court was brought by the Center for Taxpayer Rights, The Washington Post reported. The plaintiffs brought the case in February 2025.

Kollar-Kotelly wrote in her opinion, “The IRS violated the [Internal Revenue Code] approximately 42,695 times by disclosing last known taxpayer addresses to ICE … without confirming that ICE’s request set forth the ‘address of the taxpayer with respect to whom the requested return information relate[d].’”

The Trump administration defended data sharing in a statement last May after U.S. District Judge Dabney Friedrich first rejected the motion for a temporary injunction by Centro de Trabajadores Unidos.

“Information sharing across agencies is essential to identify who is in our country, including violent criminals, determine what public safety and terror threats may exist so we can neutralize them, scrub these individuals from voter rolls, and identify what public benefits these aliens are using at taxpayer expense,” Department of Homeland Security spokeswoman Tricia McLaughlin said in a statement.

“With the IRS information specifically, DHS plans to focus on enforcing long-neglected criminal laws that apply to illegal aliens but which the Biden Administration ignored.”