This article reflects Oklahoma law and enforcement conditions as of June 2026. Oklahoma has enacted some of the most aggressive state-level immigration enforcement in the country and is actively litigating the constitutionality of its core law. Key facts: House Bill 4156 (signed April 2024 by Gov. Kevin Stitt) created the state crime of 'impermissible occupation' - making it a misdemeanor for any undocumented person to be present in Oklahoma, with felony penalties for second offenses, and a mandatory requirement to leave the state within 72 hours of conviction or release from custody. HB 4156 was blocked by a federal preliminary injunction from June 2024 through March 2025. The Trump DOJ dropped the Biden-era federal lawsuit on March 14, 2025, dissolving the injunction. Civil rights groups (ACLU of Oklahoma, Padres Unidos de Tulsa) refiled suit; a federal judge issued a second temporary restraining order on May 20, 2025. That litigation was ongoing as of June 2026 - verify the current enforcement status of HB 4156 at the ACLU of Oklahoma (acluok.org) before relying on any account of whether the law is enforceable. Operation Guardian: Gov. Stitt directed DPS Commissioner Tim Tipton in November 2024 to create a statewide immigration enforcement plan. On February 21, 2025, Oklahoma finalized 287(g) agreements with three state agencies - the Oklahoma Department of Public Safety (including Oklahoma Highway Patrol), the Oklahoma Bureau of Narcotics (OBN), and the Oklahoma State Bureau of Investigation (OSBI) - giving each agency authority to identify, arrest, and remove undocumented immigrants statewide. More than 30 local agencies held 287(g) agreements as of February 2026. OHP conducted an I-40 highway sweep resulting in more than 125 arrests. Local detentions across Oklahoma increased by nearly 200 percent in 2025 compared to the prior two years, with 1,994 people booked into 88 different local detention centers across the state. Tulsa Mayor Monroe Nichols pledged that Tulsa Police would never cooperate with federal immigration authorities on broad deportations of non-criminals, even as the Tulsa County Sheriff operates under a jail enforcement 287(g) agreement. Verify current HB 4156 litigation status and 287(g) agency list at the ACLU of Oklahoma (acluok.org) or the Oklahoma Policy Institute (okpolicy.org).
Where Oklahoma Stands
Oklahoma is one of the most enforcement-aggressive states in this series, with a combination of state criminal enforcement law, statewide agency 287(g) agreements, and an active program - Operation Guardian - designed to expand immigration enforcement through every level of Oklahoma law enforcement. At the same time, Oklahoma's core state law, HB 4156, is under active federal litigation challenging its constitutionality, and the story of that law illustrates the complexity at the intersection of state enforcement ambitions and federal preemption doctrine.
HB 4156 is the most distinctive and contested element of Oklahoma's story. It created a state crime - impermissible occupation - that essentially mirrors and punishes what is already a federal immigration violation. The Biden administration sued, a federal judge blocked the law, then the Trump administration dropped the lawsuit, dissolving the injunction. Civil rights groups immediately refiled, a second judge issued a second restraining order, and the litigation continues. Whether Oklahoma can enforce this state crime - and whether any other state can do the same - is a live constitutional question in the Tenth Circuit.
Operation Guardian is the operational layer. Three state agencies with statewide reach - DPS (including the Oklahoma Highway Patrol), OBN, and OSBI - all have 287(g) agreements authorizing them to identify, arrest, and transport undocumented immigrants. The Highway Patrol has conducted highway sweeps. The program was explicitly designed to expand to local law enforcement as well, and more than 30 local agencies had joined by early 2026. The practical effect is that any encounter with any of these agencies - a traffic stop on I-40, a narcotics investigation, a criminal inquiry - can become an immigration enforcement action.
Oklahoma's immigrant population includes significant Latino communities in Oklahoma City (especially in the southwest), Tulsa, and agricultural communities throughout the state. The state also has refugee communities resettled in Oklahoma City and Tulsa, and a significant population of immigrants from Southeast Asia, particularly in the Oklahoma City metro. Agriculture, poultry and food processing, construction, and the oil and gas service industry all employ substantial immigrant workforces.
Part 1: What Federal Immigration Law Actually Says
Immigration enforcement is exclusively a federal function under the Immigration and Nationality Act (INA). The federal government controls who may enter, remain in, and be removed from the United States. This is the foundational legal principle that makes HB 4156 constitutionally contested.
The Supremacy Clause of the U.S. Constitution, together with decades of Supreme Court precedent, establishes that federal law governing immigration is the supreme law of the land. Arizona v. United States (2012) is the controlling case: the Court held that states cannot create their own immigration enforcement schemes that conflict with federal law, and that the federal government's broad authority over immigration cannot be supplemented by parallel state criminal enforcement. The Biden-era federal judge who blocked HB 4156 in June 2024 cited this principle, ruling that Oklahoma may have understandable frustrations with illegal immigration but may not pursue policies that undermine federal law.
Section 287(g) of the INA creates the voluntary delegation mechanism through which local agencies take on immigration enforcement functions. Oklahoma's Operation Guardian 287(g) agreements for DPS, OBN, and OSBI are squarely within this framework - they are federally authorized delegations of immigration enforcement authority, not independent state enforcement. This is the legally sound part of Oklahoma's enforcement architecture. HB 4156's creation of an independent state crime, by contrast, is the legally contested part.
The Tenth Amendment anti-commandeering doctrine means the federal government cannot compel state agencies to enforce federal law. Oklahoma's 287(g) participation is voluntary - the state chose to enter the agreements. The legislature or a future governor could undo that choice. What the state cannot do, under Arizona v. United States, is create a separate and independent state criminal enforcement scheme that conflicts with or supplements federal immigration law in ways the federal government has not authorized.
ICE administrative warrants, Form I-200 and I-205, are not judicial warrants signed by judges. Under Operation Guardian, Oklahoma Highway Patrol officers can make immigration arrests authorized by their 287(g) training and federal delegation - but those arrests still require probable cause under federal immigration law. A traffic stop alone does not justify an immigration arrest; there must be reason to believe the person is in violation of immigration law.
Part 2: Oklahoma State Law
House Bill 4156 - The Impermissible Occupation Law (April 2024; Litigation Ongoing)
House Bill 4156, signed by Gov. Stitt in April 2024, created the state crime of impermissible occupation. Under the law, any person who is an alien and who willfully and without permission enters and remains in Oklahoma without first obtaining legal authorization to enter the United States commits an impermissible occupation. A first offense is a misdemeanor punishable by up to one year in county jail and/or a fine of up to $500. The person is also required to leave Oklahoma within 72 hours of conviction or release from custody. A second or subsequent offense is a felony punishable by up to two years in state prison and/or a fine of up to $1,000, plus the same 72-hour departure requirement. The law authorizes law enforcement to collect identifying information - fingerprints, photographs, biometric data - from violators, maintained by the OSBI.
The litigation history of HB 4156 is central to understanding its current status. The Biden DOJ sued on May 21, 2024, arguing federal preemption. Federal District Judge Bernard Jones issued a preliminary injunction on June 28, 2024, prohibiting enforcement. Oklahoma appealed to the Tenth Circuit. On January 23, 2025, the Trump DOJ signaled reconsideration. On March 14, 2025, the Trump DOJ voluntarily dismissed the Biden administration's lawsuit. The dismissal dissolved the preliminary injunction, making HB 4156 fully enforceable. Civil rights groups - the ACLU of Oklahoma, Padres Unidos de Tulsa, and others - filed a new federal lawsuit on May 13, 2025. Federal Judge Jones issued a second temporary restraining order on May 20, 2025. That litigation was ongoing in the Tenth Circuit as of June 2026.
Whether HB 4156 is currently enforceable depends on the status of the second civil rights injunction. Verify the current litigation status before relying on any account of the law's enforceability. The ACLU of Oklahoma (acluok.org) is the most current source. The stakes are national: if the Tenth Circuit upholds HB 4156, it could set a precedent for similar state criminal immigration laws across the country. If the court strikes it down, it affirms the limits Arizona v. United States placed on state immigration enforcement.
Even if enjoined, HB 4156's existence and the enforcement climate it has created shapes daily life for Oklahoma's immigrant communities. The law and Operation Guardian together create an environment in which immigrants fear all law enforcement encounters, not just federal agents. This chilling effect operates regardless of whether HB 4156 is technically enforceable at any given moment.
Operation Guardian - 287(g) Agreements with State Agencies (February 2025)
On February 21, 2025, Gov. Stitt announced that the Oklahoma Department of Public Safety (DPS), the Oklahoma Bureau of Narcotics (OBN), and the Oklahoma State Bureau of Investigation (OSBI) had finalized 287(g) agreements with ICE under the Operation Guardian framework. DPS includes the Oklahoma Highway Patrol (OHP), giving the state a statewide law enforcement force with immigration arrest authority. The OBN and OSBI agreements extend that authority to the state's narcotics and investigations bureaus.
Under the DPS agreement, OHP troopers can interrogate, detain, and transport individuals suspected of being in the country illegally. OHP has participated in federal Homeland Security Task Forces and conducted enforcement operations on major highways including I-40. In October 2025, OHP and ICE arrested more than 125 people during an I-40 sweep and seized what the state described as unverifiable licenses. The operation was part of the ongoing Operation Guardian enforcement activity.
The scope of these agreements is broader than county jail programs. The Task Force Model in particular authorizes Oklahoma troopers to perform immigration enforcement during everyday patrol activity - traffic stops, checkpoint operations, roadside encounters. Any contact with an OHP trooper can become an immigration enforcement encounter for anyone the trooper has reason to believe may be in violation of immigration law.
Local 287(g) Agreements - Rapid Expansion
More than 30 local law enforcement agencies in Oklahoma held 287(g) agreements as of February 2026, according to the Oklahoma Policy Institute. Local detentions across the state increased by nearly 200 percent in 2025 compared to the prior two years. Federal records obtained by the Deportation Data Project showed 1,994 people arrested and booked into 88 different local detention centers across Oklahoma and flagged for immigration enforcement in 2025. The expansion from 0 to 30+ local agreements occurred almost entirely after Trump's second inauguration on January 20, 2025. Agreements include agencies in Tulsa County, Canadian County, Vinita, Sterling, and other communities. Most operate under Jail Enforcement Model agreements, though some include Task Force authority. Verify the current list of Oklahoma 287(g) agencies at the Oklahoma Policy Institute (okpolicy.org) or the ACLU of Oklahoma.
Tulsa - A Counter-Posture Within Oklahoma
Tulsa presents the most significant internal division in Oklahoma's enforcement picture. Mayor Monroe Nichols, former state representative who won the Tulsa mayoral race, pledged shortly after his election that Tulsa Police Department officers would never cooperate with federal immigration authorities on broad deportations of non-criminals. He stated directly: 'Looking over the shoulder of folks and asking about their immigration status is just not something that we're ever going to be involved in.' This posture applies to Tulsa Police and city government - but not to the Tulsa County Sheriff's Office, which operates under a Jail Enforcement 287(g) agreement with ICE. As of late July 2025, 440 people had been detained at the David L. Moss Justice Center (Tulsa County jail) under the sheriff's ICE cooperation agreement. The practical result: Tulsa residents arrested by city police face a different enforcement risk than those arrested by the county sheriff or stopped by OHP troopers.
Existing Statutory Basis for County Jail Cooperation
Oklahoma statute 57 O.S. section 16a authorizes county jails to hold ICE detainees. This existing state law provides the legal basis for county jails to honor ICE detainers - the question of whether any individual county does so is a matter of that county's policy and any 287(g) agreement in place. This pre-existing statutory authority, combined with Operation Guardian and the 287(g) expansion, means the legal infrastructure for cooperation between Oklahoma local jails and ICE is comprehensive and does not depend solely on HB 4156.
Part 3: How State and Federal Law Interact in Oklahoma
Oklahoma's enforcement framework operates on two distinct legal tracks. The 287(g) track - Operation Guardian agreements with DPS, OBN, OSBI, and the local agency agreements - is on sound legal footing under the INA's section 287(g) delegation mechanism. These agreements are federally authorized, supervised by ICE, and consistent with Arizona v. United States. They represent enforcement expansion within the constitutional framework.
The HB 4156 track is legally contested. The core question is whether a state can create a criminal offense that mirrors a federal immigration violation and allow state officers without 287(g) training to arrest and prosecute people under state law for what is already a federal crime. The Tenth Circuit's resolution of this question may ultimately set national precedent. If HB 4156 is upheld, any state in the circuit could create similar laws. If struck down, it reaffirms that states cannot supplement federal immigration law with parallel state criminal enforcement outside the 287(g) framework.
Even if HB 4156 is enjoined, the enforcement consequences in Oklahoma are significant through Operation Guardian and local 287(g) agreements alone. State troopers, narcotics agents, and investigators all have federal immigration arrest authority. More than 30 local agencies have jail enforcement agreements. Local detentions increased 200 percent in 2025. The state's enforcement infrastructure does not depend on HB 4156 to be powerful.
Tulsa's mayoral posture illustrates the internal variation. Within the same county, Tulsa Police will not ask about immigration status while the county sheriff operates an active jail enforcement agreement. This kind of jurisdiction-by-jurisdiction variation is typical in states without a statewide mandatory cooperation mandate.
Part 4: What This Means for Families on the Ground
For immigrant families in Oklahoma, the enforcement picture is among the most acute in this series. OHP troopers with Task Force authority can make immigration arrests during routine traffic stops statewide. Local 287(g) jails in more than 30 jurisdictions create a jail-to-ICE pipeline for anyone booked on state charges. Local detentions increased 200 percent in 2025 with nearly 2,000 people processed through 88 different facilities.
HB 4156's current enforceability must be verified at the time of reading. If the second civil rights injunction is in place, the state crime of impermissible occupation is temporarily blocked. If the injunction has been lifted or dissolved, any undocumented person in Oklahoma is subject to state criminal arrest by any law enforcement officer - not just 287(g)-trained officers - on the state misdemeanor charge. This creates a fundamentally different enforcement risk than states without such a law.
Highway travel across Oklahoma carries elevated risk. OHP troopers have Task Force authority statewide, and Operation Guardian has specifically targeted I-40 and other major highways. The I-40 corridor, which runs east-west through Oklahoma City, is a documented enforcement zone.
Agricultural communities in western Oklahoma, food processing operations in the southwest, oil and gas service workers throughout the state, and the poultry industry in eastern Oklahoma all represent concentrations of immigrant workers who face elevated enforcement risk.
Oklahoma City and Tulsa have large Latin American immigrant communities. In Oklahoma City, the southwest side has a dense concentration of immigrant families. Tulsa's Greenwood area and northeast Tulsa have significant immigrant communities. The Tulsa mayor's non-cooperation posture for city police provides some protection for Tulsa residents interacting with city officers - but not county sheriffs or state troopers.
Part 5: What You Can Actually Do
If Stopped by an Oklahoma Highway Patrol Trooper
Oklahoma Highway Patrol troopers have 287(g) Task Force authority and can ask about your immigration status and make immigration arrests during routine traffic stops. Provide your driver's license and vehicle documents when requested. You have the right to remain silent about your immigration status beyond providing identification. Say: 'I am exercising my right to remain silent about my immigration status. I want to speak with a lawyer.' Do not physically resist.
If you are being detained, ask clearly: 'Am I being detained or am I free to go?' If being detained, do not answer questions about your immigration status. Request an attorney. Do not sign any documents without speaking with an attorney.
If ICE or OHP Comes to Your Home
Do not open the door. ICE cannot legally enter a home without a judicial warrant signed by a judge. An administrative warrant, Form I-200 or I-205, is signed by an immigration officer, not a judge, and does not authorize home entry. Ask through the closed door whether the warrant is signed by a judge. If not, say clearly that you do not consent to entry.
You have the right to remain silent. You are not required to answer questions about your birthplace, how you entered the country, or your immigration status. Say: 'I am exercising my right to remain silent. I want to speak with a lawyer.'
Do not sign anything without speaking with an immigration attorney. Signing voluntary departure forms can permanently waive important legal rights.
If Arrested in Oklahoma
If arrested, you may be booked into a county jail with a 287(g) agreement. Request a lawyer immediately. Do not answer questions about your immigration status during booking beyond what is legally required. Have the phone number of an immigration attorney or the ACLU of Oklahoma accessible to family members before any encounter occurs.
Know the current status of HB 4156. If the injunction is in place, the state crime of impermissible occupation is blocked and officers cannot arrest you solely for being undocumented under state law. If the injunction has been lifted, any officer - not just 287(g)-trained officers - can potentially make a state criminal arrest. Verify the status at acluok.org.
If a Family Member Is Detained
Use the ICE Online Detainee Locator at locator.ice.gov immediately. Detainees in Oklahoma may be held at local county jails with ICE agreements or transferred to federal facilities in Texas or elsewhere. Act quickly.
Call the ICE Detention Reporting and Information Line: 1-888-351-4024.
Call the EOIR Immigration Court Information Line: 1-800-898-7180.
Contact the ACLU of Oklahoma: acluok.org. The ACLU-OK is lead plaintiff in the civil rights litigation against HB 4156 and the primary enforcement monitoring resource in Oklahoma.
Contact Padres Unidos de Tulsa: the original plaintiff group in the HB 4156 litigation and a community organizing resource for Tulsa-area immigrant families.
Contact the Oklahoma Policy Institute: okpolicy.org. OK Policy tracks immigration legislation, 287(g) agreements, and enforcement conditions statewide.
Contact Catholic Charities of the Archdiocese of Oklahoma City: catholiccharitiesok.org. Catholic Charities provides direct immigration legal services and support.
Know the Risk Points in Oklahoma
OHP troopers have Task Force 287(g) authority statewide. Any traffic stop on any Oklahoma highway can become an immigration enforcement encounter.
HB 4156 enforcement status is uncertain. Verify with the ACLU of Oklahoma whether the state crime of impermissible occupation is currently blocked by injunction before relying on this article.
Over 30 local agencies have jail enforcement 287(g) agreements. Any jail booking in those jurisdictions creates direct ICE contact.
The I-40 corridor is a documented enforcement zone. OHP and ICE have conducted specific highway sweeps producing 125+ arrests at a time.
Tulsa city police will not ask about immigration status per the mayor's directive - but the Tulsa County Sheriff's jail does cooperate with ICE under a 287(g) agreement.
Part 6: Legal Resources in Oklahoma
ACLU of Oklahoma: acluok.org. Lead plaintiff in the HB 4156 civil rights litigation. Primary enforcement monitoring and Know Your Rights resource for Oklahoma.
Oklahoma Policy Institute: okpolicy.org. Tracks immigration legislation, 287(g) agreements, and enforcement conditions. Published 287(g) agreement analysis as of February 2026.
Padres Unidos de Tulsa: original plaintiff group in the HB 4156 litigation; community organizing resource for Tulsa-area immigrants.
Catholic Charities of the Archdiocese of Oklahoma City: catholiccharitiesok.org. Direct immigration legal services.
Rivas and Associates Law Firm (Tulsa and Oklahoma City): private immigration law firm that represented Padres Unidos de Tulsa in the HB 4156 litigation.
Legal Aid Services of Oklahoma: legalaidok.org. Free civil legal services for low-income Oklahomans.
Immigration Advocates Network: immigrationadvocates.org.
EOIR Immigration Court Information Line: 1-800-898-7180.
ICE Detainee Locator: locator.ice.gov.
ICE Detention Reporting and Information Line: 1-888-351-4024.
Summary
Oklahoma has enacted some of the most aggressive state-level immigration enforcement in the country. House Bill 4156 (April 2024) created the state crime of impermissible occupation, making unlawful presence in Oklahoma a misdemeanor for first offenses and a felony for subsequent ones, with mandatory departure from the state within 72 hours of conviction. The law was blocked by federal injunction from June 2024 through March 2025, when the Trump DOJ dropped the Biden-era lawsuit dissolving the injunction. Civil rights groups immediately refiled; a second restraining order was issued May 20, 2025. As of June 2026, HB 4156's enforceability depended on the active litigation status - verify at acluok.org.
Operation Guardian: In February 2025, Oklahoma finalized 287(g) agreements with DPS (including Oklahoma Highway Patrol), OBN, and OSBI - giving these statewide agencies immigration arrest authority. More than 30 local agencies hold agreements as well. Local detentions increased 200 percent in 2025 and 1,994 people were processed through 88 facilities statewide. OHP conducted an I-40 sweep arresting 125+ people. Tulsa Police will not cooperate with ICE under the mayor's directive, but the Tulsa County Sheriff's jail does. For families in Oklahoma, the risk is acute at traffic stops (OHP has Task Force authority), at any jail booking in a 287(g) jurisdiction, and potentially through HB 4156 state criminal enforcement if the injunction is lifted. Contact the ACLU of Oklahoma for current litigation status and use the ICE Detainee Locator immediately if a family member is detained.
Sources and verification: Oklahoma HB 4156 (signed April 2024; text at Oklahoma Legislature website); Gov. Stitt announcement, 'Governor Stitt Announces Finalized Agreements with the Department of Homeland Security and ICE,' February 21, 2025 (oklahoma.gov); Operation Guardian plan (oklahoma.gov/content/dam/ok/en/governor/documents/Operation Guardian.pdf); KOSU, 'State-Level Immigration Enforcement Officially Kicks Off in Oklahoma,' February 27, 2025; KOSU, 'DOJ Drops Federal Immigration Lawsuit; New Oklahoma Crime Impermissible Occupation in Full Effect,' March 19, 2025; Oklahoma Voice, 'Federal Judge Temporarily Blocks Oklahoma Immigration Law,' May 20-21, 2025 (second TRO); Southwest Ledger, 'New Oklahoma Immigration Law Enjoined,' February 25, 2025 (Biden-era litigation timeline); KOSU/The Frontier, 'How Oklahoma's State Law Tied Up in the Courts Could Impact Immigration Enforcement,' October 24, 2025 (21 agreements, 1,994 bookings, 200% increase, Tulsa mayor quote); News9.com, 'What Is Operation Guardian?' September-October 2025 (OHP I-40 sweep 125+ arrests); Oklahoma Policy Institute, '287(g) Agreements,' February 24, 2026 (30+ agencies as of February 2026); HPPR/KGOU, 'Oklahoma's Top Public Safety Official Releases Plan for State-Level Immigration Enforcement,' February 6, 2025; Federal District Judge Bernard Jones preliminary injunction, June 28, 2024; Arizona v. United States, 567 U.S. 387 (2012); Printz v. United States, 521 U.S. 898 (1997). Volatile items requiring verification: HB 4156 second injunction/restraining order current status (pending as of June 2026; verify at acluok.org); Tenth Circuit decision on HB 4156 if appeal has been decided; current list of Oklahoma 287(g) agencies (30+ as of February 2026; growing); any additional state legislation from the 2026 session (Sen. Deevers introduced five America First immigration bills for the 2026 session - verify status at oklegislature.gov). Last verified: June 2026.