Senator Markwayne Mullin Warns Sanctuary City Airports Could Disrupt Customs Operations

(UNITED STATES) — Homeland Security Secretary Markwayne Mullin said on April 6, 2026, that his department will scrutinize customs operations at major airports in sanctuary cities, raising the prospect that some of the country’s busiest international gateways could face federal pressure over local immigration policies.

During his first interview as secretary, Mullin questioned whether cities that do not cooperate with federal immigration enforcement should continue handling international arrivals through their airports. “If they’re a sanctuary city, should they really be processing customs into their city?” he said.

Mullin tied airport customs operations to local cooperation with federal authorities, arguing that cities receiving international flights must work with the federal government at the airport and beyond. If they refuse to enforce immigration policies afterward, he said, the Department of Homeland Security may need to “have a really hard look at that” and could prioritize jurisdictions that cooperate.

He also said, “I believe sanctuary cities, it’s not lawful,” signaling a harder line from the department under his leadership.

Mullin assumed the DHS post in late March 2026 after President Trump dismissed Kristi Noem. His remarks came in his first interview as secretary with Bret Baier.

The comments immediately cast attention on how immigration enforcement disputes could spill into customs operations, an area that affects international travelers, airport authorities and local governments. Mullin’s wording suggested DHS could examine whether federal customs processing should remain in cities that limit cooperation with immigration enforcement.

Among the examples raised by his remarks were Los Angeles International Airport and John F. Kennedy International Airport, both in sanctuary jurisdictions. JFK processes roughly 3 million people through customs monthly, according to Port Authority data.

Other airports that could fall under the same scrutiny are in San Francisco, Denver, Boston, Chicago, New York, Seattle, Portland, New Orleans, Philadelphia, and Minneapolis. Mullin did not lay out an implementation plan in his remarks, but he confirmed the possibility that major airports in sanctuary cities could lose customs services.

Asked directly whether big sanctuary cities with major airports might lose those services, Mullin said that was a possibility and said he would make “hard decisions” within congressional policies. That answer sharpened concern around what such a review of customs operations could mean for cities that have long clashed with federal officials over immigration enforcement.

His remarks also brought new attention to the broader conflict over sanctuary cities, a term used for jurisdictions that limit cooperation with some federal immigration actions. As of federal recognition last August, sanctuary jurisdictions included 12 states plus Washington, D.C., four counties, and 18 cities.

That scope means the issue extends well beyond one or two airports. It reaches across multiple levels of government, including states, counties and cities that have adopted policies at odds with federal enforcement goals.

Mullin framed the issue as one of partnership with federal authorities. His argument was that a city cannot benefit from processing international arrivals and federal customs activity at its airport while refusing to support immigration enforcement after travelers leave that federal checkpoint.

That position, as he described it, could shift DHS attention toward jurisdictions more willing to work with federal authorities. In practical terms, his comments pointed to a possible sorting of cities based on whether they cooperate with immigration policies.

The remarks prompted criticism from opponents, who cast them as retaliation against sanctuary jurisdictions. Critics including The Daily Beast framed the comments as potential “sabotage” of America’s biggest airports in response to local sanctuary policies.

Mullin, however, presented his argument as part of a broader public safety mission. He complained that DHS faces political resistance despite what he described as efforts to secure streets and prevent terrorism.

That juxtaposition — customs operations at airports on one side, local immigration policy on the other — gave the remarks weight beyond a routine television appearance. The head of DHS was not only criticizing sanctuary cities in general terms; he was linking that criticism to customs operations at airports that serve millions of travelers.

For airports such as JFK and Los Angeles International, the comments carried particular force because of the volume and visibility of their international traffic. A federal review of customs operations in such places would touch transportation hubs that are central to travel and commerce.

Mullin’s language also suggested he sees the issue through a legal lens as well as a policy one. “I believe sanctuary cities, it’s not lawful,” he said, framing his position in categorical terms rather than as a narrow dispute over administrative cooperation.

That statement may matter as much as the customs comments themselves. It indicates that under Mullin, DHS could approach sanctuary jurisdictions not simply as reluctant partners but as places that, in his view, stand outside lawful bounds.

So far, neither DHS nor Customs and Border Protection has commented publicly on implementation following Mullin’s remarks. No public steps have been announced by either agency since the interview.

That leaves local officials, airport operators and travelers without a formal outline of what scrutiny of customs operations would involve. Mullin’s comments nonetheless marked a clear warning that sanctuary city policies could draw a new form of federal pressure.

The warning came early in his tenure. Because the interview was Mullin’s first as secretary, the exchange offered one of the earliest indicators of how he may use the office and which fights he intends to elevate.

His choice of subject was notable. Rather than limit his comments to broader immigration enforcement, Mullin tied sanctuary city disputes to customs operations, an area that sits at the front line of international arrivals and falls within the daily work of federal officers at major airports.

That connection could widen the debate over sanctuary cities by bringing airport operations into the argument. It also places customs operations — a technical but highly visible part of border enforcement — alongside one of the country’s most contested immigration issues.

The potential reach is broad. Airports in San Francisco, Denver, Boston, Chicago, New York, Seattle, Portland, New Orleans, Philadelphia, and Minneapolis were cited as other locations that could be affected by the kind of scrutiny Mullin described.

Those cities span different regions and political environments, but they share one feature in this discussion: sanctuary policies that have put them at odds with federal immigration priorities. Mullin’s remarks suggested those differences may now carry consequences for how DHS views customs operations.

The comments also landed at a time when sanctuary cities remain a live national issue rather than a settled one. Federal recognition last August counted 12 states plus Washington, D.C., four counties, and 18 cities as sanctuary jurisdictions, showing how wide the policy divide remains.

Because customs processing is a federal function, any move in that area would place DHS and CBP at the center of the dispute. Yet without public follow-up from either agency, the immediate effect of Mullin’s comments was to create uncertainty rather than announce a change.

Even so, the message was plain. Mullin said DHS will scrutinize customs operations in sanctuary cities, said he could make “hard decisions” within congressional policies, and asked whether cities that reject federal immigration cooperation “should they really be processing customs into their city?”