How ICE Detention Works and Who Runs the Detention Centers

On March 1, 2003, a federal agency that most Americans had never heard of simply stopped existing. The Immigration and Naturalization Service, which had handled everything from green cards to border patrols since the 1930s, was dissolved, and its pieces were handed to the brand-new Department of Homeland Security. One of those pieces got a name that was clunky enough to sound temporary: U.S. Immigration and Customs Enforcement. Nobody at the ribbon-cutting was thinking about county jails in rural Louisiana, a prison company's quarterly earnings call, or a tent complex on an Army base in El Paso. Yet that is where the story of ICE detention leads, because the agency born that spring does not own most of the places where it locks people up. It rents them.

In short: ICE holds people under civil immigration law, not criminal sentences, and it does so mostly in facilities it does not run: county jails paid by the day and large centers operated by private companies. Money and bed contracts shape how many people are held, while the offices meant to watch over conditions have always been small. Knowing who runs a facility is the first step to holding anyone accountable for it.

A civil system that looks like a prison

The first thing to understand is the legal category. Immigration detention is civil. A person held by ICE is not serving a sentence and, in most cases, has not been charged with a crime. They are being held, in the government's framing, to make sure they show up for immigration court or to carry out a removal order. Some have criminal records; many do not. Some arrived last month; some have lived in the same town for twenty years and were picked up at a traffic stop or a check-in appointment.

Civil status matters in law. It means detainees do not get a public defender, because the right to appointed counsel belongs to criminal defendants. It means the rules on conditions come mainly from agency standards and contracts, rather than from the body of prison case law built up over decades. And it means the government has argued, repeatedly, that detention is administrative rather than punitive.

In daily life, though, the difference can be hard to see. Detainees wear uniforms, sleep in cells or dormitory pods, are counted several times a day, and are moved between facilities in shackles. Many are held in the very same county jails as people awaiting criminal trial, sometimes in the same housing units. A civil label on paper does not change the cinder block.

Congress has also written some detention into law as mandatory. The 1996 immigration overhaul required detention for broad groups of people, including many with certain criminal convictions, and for people in expedited removal while their fear claims are screened. For others, ICE has discretion: it can release someone on bond, on their own recognizance, or into an alternatives program with check-ins or electronic monitoring. How that discretion is used is a policy choice, and it swings hard from one administration to the next.

Four kinds of building, one agency

ICE uses a vocabulary that sounds bureaucratic but tells you exactly who holds the keys. Broadly, there are four arrangements.

Service processing centers are owned by ICE itself. There are only a handful of them, and even several of those use private contractors for guards and food.

Contract detention facilities are owned or run by private companies under direct contracts with ICE. The two biggest names in this business are GEO Group and CoreCivic, the company that was called Corrections Corporation of America until it renamed itself in 2016. Both are publicly traded, both report detention revenue to shareholders, and both operate some of the largest centers in the system.

Intergovernmental service agreements, usually shortened to IGSAs, are deals between ICE and a local government, typically a county or a city. The county agrees to hold immigration detainees in exchange for a daily rate per person. Sometimes the county uses its own jail and its own deputies. Sometimes the county signs the agreement and then subcontracts the actual operation to a private company, so the public name on the contract is not the operator inside the walls. Reporters and researchers have spent years untangling these pass-through deals, because they let a private operator run a facility without a direct federal contract.

U.S. Marshals Service agreements allow ICE to piggyback on jail space the Marshals already rent for federal criminal defendants. A county jail with a Marshals contract can take ICE detainees under that same paperwork.

Add to these the short-term holding rooms at ICE field offices, Border Patrol stations run by a different agency, and, more recently, temporary sites. In 2025, Florida built and opened a state-run detention camp on an airstrip in the Everglades that its officials nicknamed "Alligator Alcatraz," and the federal government opened a large tent facility at Fort Bliss in Texas. These sites stretched the list of who runs immigration detention to include state emergency agencies and the military's own land.

Paying by the bed

Detention is bought one bed at a time. A county or company is paid a daily rate per detainee, and many contracts include a guaranteed minimum: ICE pays for a set number of beds whether or not they are filled. Critics call these guaranteed minimums lockup quotas, because an empty paid-for bed is money wasted, and that creates pressure to fill it. Defenders say the guarantees are the price of getting operators to build and staff capacity that the government may need suddenly.

For several years Congress itself set a floor. Starting around the end of the 2000s, appropriations language directed ICE to maintain a fixed number of detention beds, a requirement known as the bed mandate, which climbed to 34,000. Few federal programs had their size written into law that way. It became a lightning rod; immigrant-rights groups and some budget hawks both questioned why Congress was ordering an agency to hold a certain number of people regardless of need.

For a county, the math can be appealing. A rural jail with empty cells can turn them into a revenue line that helps cover deputies' salaries or a new roof. For a company, detention is a contract business with long terms and a single, deep-pocketed customer. Neither is irrational. But both create a constituency that benefits from more detention, and that constituency calls members of Congress, gives to campaigns and testifies at county board meetings. The incentive does not dictate any single decision; it tilts the field.

Money arrived in a new volume in 2025. The large budget law Congress passed and President Trump signed that July, sometimes called the One Big Beautiful Bill Act, set aside roughly $45 billion for immigration detention over several years, an amount far larger than ICE's previous detention budgets. The detained population climbed to record levels during 2025. When the money for beds grows that fast, the question of who will supply the beds answers itself: the counties and companies that already know how.

The case for detention, stated fairly

People who support a large detention system make an argument worth taking seriously. Immigration law, they say, means little if people ordered removed simply do not leave, and some people released while their cases are pending do not come back to court. Detention guarantees appearance. They add that some detainees have serious criminal records and pose real risks, that border surges overwhelm any system that relies on voluntary check-ins, and that a government unwilling to detain anyone invites more unlawful crossings.

Here is the answer, and it is an argument rather than a settled fact. Appearance can be secured more cheaply and humanely in most cases. The government's own alternatives programs, which use reporting requirements, phone check-ins and ankle monitors, cost far less per day than a detention bed, and research on case-management programs has found high rates of court appearance, especially when people have lawyers. Detention also makes it much harder to get a lawyer at all, because many facilities are in remote places hours from the nearest immigration attorney. And the people with serious criminal records are a minority of those held; detaining everyone to catch the few is the most expensive possible way to manage risk. A system sized by contracts and budget windfalls, rather than by individual assessment, will hold people who pose no danger and would show up anyway.

Progressives also owe themselves some candour. Detention grew under presidents of both parties. Family detention was expanded during the Obama years, and the large private contracts survived several Democratic budgets. The Biden administration ordered the Justice Department to stop renewing private prison contracts, but that executive order did not reach ICE. Anyone who wants a smaller system has to argue for it in Democratic administrations too, not only in Republican ones.

Who is supposed to be watching

Every detention arrangement is supposed to follow written standards. ICE has published several sets over the years, beginning with National Detention Standards in 2000 and moving to more detailed Performance-Based National Detention Standards in 2008 and 2011. Which standard applies depends on the contract. A county jail under an older agreement may follow an older, thinner rulebook than a newer contract facility. That patchwork is one reason two detainees in the same state can have very different access to medical care, phones, law libraries and visits.

Inspection comes from several directions, none of them large. ICE has internal inspectors and contracts with outside firms to check facilities against standards. The DHS Office of Inspector General conducts unannounced inspections and has published reports describing problems such as spoiled food, overuse of segregation and inadequate medical care at specific centers. The department's Office for Civil Rights and Civil Liberties takes complaints. Congress created an Office of the Immigration Detention Ombudsman in its 2020 spending law to look into individual complaints.

Those offices have always been small relative to the system they watch, and in 2025 the administration moved to cut back several of them, announcing large staff reductions at the civil rights office and the detention ombudsman. Members of Congress have a right under appropriations law to visit facilities, and in 2025 some Democratic members fought with DHS over whether they had to give advance notice.

There is also a legal requirement that ICE report deaths in custody to Congress and publish reviews of them. Those reports are among the most detailed public windows into conditions, and they are worth reading slowly. They often describe delays in care that, step by step, look like small failures, until one is not.

Why the operator's name matters to you

It is tempting to think of ICE detention as one federal machine. It is really dozens of separate deals, each signed by someone who can be named. A county commission voted to sign an IGSA. A sheriff chose to renew it. A company bid on a contract and reports the revenue to shareholders. Each of those decision-makers is reachable in a way an abstract federal agency is not.

Local fights have changed outcomes. Some counties have ended detention agreements after public pressure and budget debates, and some states have passed laws restricting private detention or new contracts within their borders. Other counties have expanded. The point is not that every fight is won; it is that the fight is local in a way that surprises people. The person deciding whether your county jail holds immigration detainees may be on the ballot at the same election as your school board.

Corporate accountability tools apply too. Companies that run detention centers answer to shareholders, lenders and insurers, and several large banks announced over the years that they would stop financing private prison and detention operators. Whatever one thinks of that strategy, it shows that detention is part of the broader story of how corporate power works in public services: a public duty, run privately, paid by the day.

What you can do

Find out what is near you. Learn whether a county jail or contract facility in your state holds ICE detainees and under what kind of agreement. County commission minutes and sheriff's budgets often list the per-day rate. The immigration and ICE topic page gathers current reporting on facilities and enforcement.

Call the people who fund it. Detention budgets are written by Congress. Use the representatives lookup with your address to get your House member's and senators' phone numbers and contact forms, see their latest votes, and ask a specific question: do they support more oversight money, unannounced inspections and public reporting for every facility?

Back the groups doing visits and legal work. Visitation programs, bond funds and legal service providers keep people connected to the outside world. The organizations directory lists nonprofits by state under immigrants and legal aid.

Show up at the county level. If your county is weighing a new or renewed detention agreement, the public comment period at the commission meeting is where the decision is made. Bring the contract's daily rate, the guaranteed minimum, and the facility's inspection history. Elected officials notice when residents know the numbers.

Watch the courts. Challenges to detention conditions and to bond policies are moving through federal courts. The Court Watch page tracks Supreme Court opinions and the emergency docket, where several immigration cases have landed.

The agency that appeared on March 1, 2003, has grown into something its founders did not describe. But it still runs on agreements that people sign, and people who sign agreements can be asked, in public, to explain them.