Are immigration officials allowed to stop people in places wholly inside the U.S.?

U.S. Customs and Border Protection, the federal agency tasked with patrolling the U.S. border and areas that function like a border, claims a territorial reach much larger than you might imagine. A federal law says that, without a warrant, CBP can board vehicles and vessels and search for people without immigration documentation “within a reasonable distance from any external boundary of the United States.” These “external boundaries” include international land borders but also the entire U.S. coastline.

What is a “reasonable distance”?

The federal government defines a “reasonable distance” as 100 air miles from any external boundary of the U.S. So, combining this federal regulation and the federal law regarding warrantless vehicle searches, CBP claims authority to board a bus or train without a warrant anywhere within this 100-mile zone. Two-thirds of the U.S. population, or about 200 million people, reside within this expanded border region, according to the 2010 census. Most of the 10 largest cities in the U.S., such as New York City, Los Angeles, and Chicago, fall in this region. Some states, like Florida, lie entirely within this border band so their entire populations are impacted.

Your Rights in the Border Zone