With election administration under heightened national scrutiny ahead of the 2026 midterms, federal law enforcement activity around voting sites has become a new flashpoint. Denver moved into that dispute on September 10, joining civil-rights and voting-rights groups in a federal lawsuit aimed at blocking armed immigration agents from polling places. The case centers on whether even a limited ICE presence near voting locations could suppress turnout and disrupt local election operations.
Denver joins voting-rights groups in federal court challenge
The City and County of Denver joined the League of United Latin American Citizens, Common Cause and UnidosUS in a lawsuit filed Thursday, September 10, in federal district court in Washington, D.C., according to CBS News and Public Rights Project reporting on the case. The suit names the Department of Homeland Security and Immigration and Customs Enforcement, along with agency leadership, and asks a judge to bar armed federal officers from polling places and other locations where ballots are collected. The complaint argues that a post-Civil War federal statute bars officials from sending “armed men” to places where general or special elections are being held, except in the narrow circumstance of repelling armed enemies of the United States.
The filing is preemptive. Trump administration officials have not announced a blanket plan to station ICE officers at polling sites, but Homeland Security Secretary Markwayne Mullin said at a September 1 news conference in New York that ICE would not “patrol” polling places while also leaving open the possibility that agents could appear there if there were a threat or if they were serving a warrant, according to The Washington Post and CBS News. Bloomberg Law reported that the complaint also challenges the policy under federal administrative law, arguing it interferes with election administration and was not properly implemented.
For Denver, the case is about the local conduct of elections as much as it is about immigration enforcement. Court filings described in Bloomberg Law say the presence of armed ICE officers at or near voting locations could make it harder for local election officials and law enforcement to manage polling places and keep them orderly. Denver’s inclusion in the suit puts a major Colorado jurisdiction directly into a national legal fight over who controls the conditions around in-person voting.
What is confirmed is narrower than the political debate around it. There is no public announcement of a specific ICE deployment plan for Denver polling places, and no comprehensive list of affected Colorado voting locations has been released. The lawsuit instead asks the court to block any such action before ballots are cast. Public Rights Project said the challenge targets a policy that would allow armed ICE officers to serve warrants or carry out other enforcement activity during the 2026 election season, while the plaintiffs contend that possibility alone could chill participation.
The lawsuit’s core argument is that fear of contact with immigration authorities can deter lawful voters, including U.S. citizens, from approaching the polls. According to The Washington Post’s summary of the complaint, the plaintiffs point to reporting that immigration agents have wrongly detained more than 170 U.S. citizens since the administration’s immigration crackdown began, including more than 50 people who were held after agents questioned their citizenship. The complaint uses those figures to argue that voters could reasonably fear encounters with ICE even if they are legally entitled to vote.
The filing also cites recent incidents around voting activity in other states, according to The Washington Post and The New York Times, including immigration officers near an early-voting site in San Antonio, ICE vehicles outside a vote center in Simi Valley, California, and federal agents entering a Syracuse, New York, polling site in a library. For Denver residents, the immediate effect is legal rather than operational: the city is seeking a court order before November to define where armed federal immigration enforcement can and cannot occur. As of now, the administration has said ICE is not assigned to patrol polling places, while plaintiffs are asking the court to make that limit enforceable.