The Trump administration is seeking ways to use IRS data from the tax returns of immigrants who do not have a Social Security number as a tool for ICE to locate, detain, and deport them.
The effort marks a new, and boldly illegal attempt by the Trump administration to weaponize confidential administrative data to generate lists of perceived enemies.
A 2024 report to Congress by the IRS Taxpayer Advocate Service showed that in 2022, there were 3.8 million income tax returns with Individual Taxpayer Identification Numbers (ITINs), issued to individuals for federal tax purposes who are not eligible for a Social Security Number. That same year, undocumented immigrants paid more than $96.7 billion in federal, state, and local taxes.
Yet while most ITIN-based tax returns are from undocumented immigrants, not all are. At any point, tens of thousands of lawfully present immigrant workers—including unaccompanied minors—who have applied for but not yet received an SSN are, consequently, required to secure an ITIN.
Yes, access to the IRS data would make it easier for authorities to locate undocumented immigrants. It could also be illegally combined with other data sources to target anyone regardless of status. Indeed, the mix of personal and financial data on income tax returns makes them particularly sensitive—for all Americans.
The IRS has, historically, been scrupulous in safeguarding the privacy of tax filers. After a Trump-appointed Secretary of the Treasury authorized the sharing of data from an estimated 700,000 ITIN tax filers who DHS alleged without evidence were criminals or under investigation, the acting IRS Commissioner, Kathleen Krause, and the IRS Chief Privacy Officer, Kathleen Walters resigned.
The key legal issue for DHS efforts to get into ITIN taxpayers’ returns is whether the Trump administration can successfully brand all undocumented immigrants as “criminals.” They are not; research indicates that undocumented immigrants are less than half as likely as U.S. citizens to have committed a crime. FBI and Department of Justice data also show an inverse relationship between rising migration and crime rates nationally.
And in the U.S. legal system terminology does matter. In fact, for many unauthorized immigrants, entry into and residence in the U.S. is explicitly not a crime.
Litigation about use of the ITIN data is ongoing. On May 12, the DC District Court blindly accepted DHS’s assertion that it would only use the IRS data in criminal investigations, despite the fact that DHS had just expanded its’ contract with Palantir Technologies for data analysis the month before to improve targeting of non-criminals as well as felons. The decision, now being appealed, provided a blank check for invasion of privacy—the data equivalent of a traffic stop based on racial profiling.
So what would be the impact if the Trump administration is allowed access to all 3.8 million ITIN tax filers because President Trump declared them to be criminals?
The first, and most serious, impact would be to further undermine the principle of “prosecutorial discretion.”
As is the case with ICE sweeps of street corner labor markets, arrests at courthouses, and arbitrary revocation of visas, use of confidential private data degrades efforts to apprehend bona fide criminals. Many ITIN filers file ITIN returns annually to secure refunds for over-withholding of federal income tax or to be able to claim deductions for their children. Their profile is not at all like that of the incarcerated criminal population—immigrant or native-born.
The second impact would be that using ITIN data, statutorily designated as a tool to encourage paying taxes, would discourage tax compliance. ITIN filers paid almost $16 billion in federal income tax in 2023. Even modestly lowered compliance due to worries about confidentiality of personal data would increase the federal deficit by several billions of dollars. The Yale Budget Lab estimates there would be a decrease of $25 billion in income tax revenue in the 2026 fiscal year.
The third impact of unwarranted ICE use of privacy-protected and sensitive personally-identifiable data from immigrant households—including mixed-status homes where one or more family member is a US citizen—would be to accelerate the already-catastrophically low public trust in federal government.
More than two-thirds of Americans are already concerned about how the government uses data it collects from them and feel they have no control about how it’s used. Duplicitous exploitation of exceptions to the Privacy Act safeguards on misuse of personal data would further erode trust.
ICE efforts to secure privacy-protected IRS data for immigration law enforcement need to be recognized as what they are; not simply an assault on undocumented immigrants, but an assault on everyone’s civil liberties.
Edward Kissam is a leading researcher and advocate for strategies to deal with health issues impacting immigrant communities. He has led research on farmworker and immigrant issues sponsored by the Department of Labor, the Commission on Agricultural Workers, and the National Institute for Food and Agriculture. He is also a trustee of the WKF Charitable Giving Fund.
