The U.S. Supreme Court on Friday reinstated an expanded immigration database that President Donald Trump’s administration aims to combat voting by noncitizens, but which critics say could disenfranchise voters.
The justices granted the Justice Department’s request to block a judge’s order preventing state authorities from using information such as Social Security numbers to comb through registered voters’ citizenship status against federal records.
The court has a 6-3 conservative majority. Three liberal justices dissented from Friday’s order.
The majority said the plaintiffs’ claims were likely to fail because federal law explicitly authorizes the Department of Homeland Security to request and receive information about citizenship and immigration status from other agencies, including the Social Security Administration.
The administration’s data-sharing agreement is one of a series of steps to increase federal involvement in voting ahead of November’s midterm elections, when President Trump’s fellow Republicans aim to maintain control of Congress. The U.S. Constitution gives states the primary authority to conduct and administer elections.
Last year, the Department of Homeland Security redesigned the federal database used to verify individuals’ citizenship and immigration status, known as Systematic Alien Verification for Entitlements (SAVE). With this improvement, users can now search many records at once and perform searches using an individual’s social security number.
Since then, several Republican-led states have checked their voter lists against databases, and some voters marked as possible non-citizens have been deregistered.
Critics argue that such election-related actions by Republicans are driven less by concerns about election security and more by attempts to gain political advantage by narrowing districts at the risk of disenfranchising voters, often Democratic-leaning voters.
President Trump has pursued hard-line immigration policies and falsely claimed widespread voter fraud, including in the 2020 election, which he lost to Democratic former President Joe Biden.
Advocacy groups that filed a lawsuit to block the revised SAVE system said the new approach resulted in people unfairly identified as non-citizens being removed from voter rolls. They argue that SAVE may be outdated and means that immigrants who are naturalized U.S. citizens and eligible to vote may be considered non-citizens.
The overall error rate of the modified system has not been made public. The Department of Homeland Security and the Department of Justice did not provide that information in response to inquiries.
Citizens for Responsibility and Ethics in Washington, which represents the plaintiffs, called Friday’s decision “deeply disappointing” and said it puts Americans “at risk of being illegally targeted by the administration’s unreliable voter purge database in the weeks before the midterm elections.”
“The harm caused by burdening or disenfranchising even a small number of legal voters outweighs the nonexistent harm that the government suffers when it is prevented from taking actions it probably does not have the power to take,” Justice Ketanji Brown Jackson wrote in a dissenting opinion joined by two of his fellow liberal justices on Friday.
In a Supreme Court filing, the advocacy group cited election officials in Travis County, Texas, who said 25% of the system’s matches for noncitizens there involved people who had already proven their U.S. citizenship, and news reports that at least 81% of the system’s responses in St. Louis County, Missouri, were incorrect.
The League of Women Voters, a voting rights group, and the Electronic Privacy Information Center, a privacy rights group, filed a lawsuit in September 2025 seeking to block the Trump administration’s altered system. They argued that the revamp violates federal privacy and other U.S. laws.
In a June ruling blocking the revamped database, U.S. District Judge Sparkle Skunanan in Washington, D.C., said the system was haphazardly assembled and contained unreliable citizenship data.
“Overall, the federal government is willfully trampling on Americans’ privacy rights in a way that threatens their sacred right to vote,” Skunanan wrote. “This court cannot stand by and watch that happen.”
On September 4, the U.S. Court of Appeals for the District of Columbia Circuit refused to block Sukunanan’s sentence in a 2-1 decision, and the government asked the Supreme Court to do so.
In a Supreme Court filing, Justice Department lawyers argued that the judge’s order was “indefensible” and “threatened the integrity” of the midterm elections.
The state of Texas, which intervened in the case in support of the administration, disputes claims that the system is unreliable.
A separate lawsuit in Florida allowed the Trump administration to continue using the modified SAVE system in Republican-led states of Florida, Iowa, Indiana and Ohio.
