Every county in Colorado is a sanctuary county in the practical sense that matters most: statewide laws restrict local police, sheriffs, and jails from helping federal agents enforce civil immigration law, and those restrictions apply the same way in all 64 counties. A few cities and counties, Denver and Pitkin among them, have added their own resolutions on top. But the baseline protections do not change when you cross a county line.
That is the short answer. The longer answer is worth understanding, because the word “sanctuary” gets used loosely, and the gap between what local law enforcement cannot do and what federal agents still can do is where most confusion lives.
What “Sanctuary County” Means in Colorado
In many states, sanctuary status is a city-by-city or county-by-county question. In Colorado it is mostly a state-law question. Because the legislature has set uniform rules on immigration detainers, detention agreements, and release procedures, a sheriff in Weld County and a sheriff in Denver face the same statutory limits. The label “sanctuary county” typically gets attached to places that have passed their own resolutions or ordinances on top of state law, but a county without a resolution still follows the same core rules.
The practical difference between a county with its own sanctuary resolution and one without is mostly policy posture and internal protocol. A county that has adopted a resolution may have additional rules, such as forbidding officers from asking about immigration status in any encounter or refusing to share non-public information with federal authorities without a judicial warrant. Counties that have not adopted resolutions still have to follow state law, which produces much of the same result.
The State Laws That Apply Everywhere
Three state laws form the backbone of Colorado’s framework, and they apply in every county.
HB 19-1124: No Holds on ICE Detainers
Signed in 2019, HB 19-1124 prohibits any Colorado law enforcement officer from arresting or detaining someone based solely on a civil immigration detainer request from ICE. Those detainer requests are administrative forms, not judicial warrants. Colorado law treats holding someone past their release date on a detainer as a warrantless arrest, which the legislature declared unconstitutional based on prior Colorado Supreme Court precedent.1Justia. Colorado Code 24-76.6-102 – Civil Immigration Detainers – Legislative Declaration
The law does not block all cooperation. Officers can still assist federal authorities who present a warrant signed by a federal judge or magistrate, and they can honor any writ from a state or federal judge ordering a prisoner transfer. Officers also remain free to investigate and enforce criminal laws, including joint operations with federal agencies targeting criminal activity.1Justia. Colorado Code 24-76.6-102 – Civil Immigration Detainers – Legislative Declaration A judicial warrant based on probable cause still works. An ICE administrative form does not.
The same law restricts probation officers and probation department employees from providing personal information about individuals to federal immigration authorities. If federal agents want to interview someone in a jail or custodial facility, the individual must be told that the interview is being sought by immigration authorities, that they can decline and remain silent, that they can speak with an attorney first, and that anything they say could be used in immigration proceedings.2Colorado General Assembly. HB19-1124 Protect Colorado Residents From Federal Government Overreach
HB 23-1100: No Local Role in Immigration Detention
Effective January 1, 2024, HB 23-1100 prohibits any state or local government entity from entering into agreements for the detention of individuals in privately operated immigration detention facilities. It also bars government entities from selling property for private immigration detention facilities, paying costs related to building or running them, receiving payment for detaining people for civil immigration purposes, or providing financial incentives to private detention operators.3Colorado General Assembly. HB23-1100 Restrict Gov Involvement In Immigration Detention
Any existing immigration detention agreement had to be terminated by January 1, 2024, or as soon as the contract terms allowed. Local governments can still provide health and safety resources to people being detained for immigration purposes and can contract for health, utility, and sanitation services to detention facilities.3Colorado General Assembly. HB23-1100 Restrict Gov Involvement In Immigration Detention
SB 25-276: No Slow-Walked Releases
SB 25-276, passed in 2025, prohibits jail custodians from delaying a defendant’s release for the purpose of an immigration enforcement operation.4Colorado General Assembly. SB25-276 Protect Civil Rights Immigration Status Where the 2019 law focused on detainers, this one closes a quieter tactic: jail staff slowing down release paperwork to coordinate timing with ICE.
Counties and Cities That Have Gone Further
A handful of Colorado jurisdictions have adopted their own policies on top of state law. These are the places most often described as “sanctuary” in media and in federal government lists.
Denver
The City and County of Denver has the most developed local framework. Denver Executive Order No. 142 and Denver Ordinance No. 940-17 establish the city’s immigration enforcement policies on top of state law. The city describes itself as a “welcoming city” and states that city employees do not enforce federal immigration laws, that police officers do not ask about immigration status during routine encounters, and that the city does not inquire about immigration status unless required by law.5City and County of Denver. Denver’s Federal Immigration Enforcement Response Denver’s policies were specifically named in a 2025 federal lawsuit challenging Colorado’s sanctuary framework.
Pitkin County
Pitkin County’s Board of County Commissioners passed a resolution in 2017 affirming the county as a welcoming community for immigrants. The resolution is detailed: county departments and personnel cannot perform the functions of a federal immigration officer or participate in the 287(g) program, the sheriff’s office cannot stop or arrest someone based solely on suspected immigration status or a civil immigration warrant, and no county department can share non-public information such as release dates, home addresses, or work addresses with ICE or CBP unless accompanied by a judicial warrant. The resolution also bars the sheriff from delaying bail or release for immigration enforcement purposes.
Boulder County
The city of Boulder passed a sanctuary city declaration, and Boulder County commissioners have publicly stated the county complies with federal immigration law while pushing back against federal characterizations of the county as noncompliant. Boulder County appeared on a federal list of sanctuary jurisdictions despite the county’s position that it follows the same state laws as every other Colorado county.
What Happens at the Jail
The jail is where Colorado’s sanctuary laws have their most visible effect, and the rules there are the same in every county.
When someone finishes their sentence, posts bond, or is otherwise eligible for release, jail staff must let them go on schedule. They cannot hold the person an extra hour to give federal agents time to arrive, even if ICE has filed a detainer request.1Justia. Colorado Code 24-76.6-102 – Civil Immigration Detainers – Legislative Declaration They also cannot slow-walk the release process to accommodate an immigration enforcement operation.4Colorado General Assembly. SB25-276 Protect Civil Rights Immigration Status
Facility staff are restricted from sharing non-public information with federal immigration authorities. An inmate’s release date, home address, or work address cannot be provided to ICE or CBP unless the information is available to the general public or the request is backed by a judicial warrant. If a federal agent wants to take custody of someone, that agent needs a warrant signed by a judge. An administrative warrant signed by another ICE agent does not meet that standard under Colorado law.
Counties that violate these restrictions expose themselves to litigation for unlawful detention, which gives sheriffs and jail administrators a direct financial incentive to follow the release rules carefully, even in counties where local officials might otherwise prefer to cooperate with ICE.
What Happens During Police Encounters
On the street, officers performing routine duties such as traffic stops or investigating minor offenses are not supposed to inquire about a person’s citizenship or immigration status for the purpose of enforcing civil immigration law. This is department policy across the state. The Colorado Springs Police Department’s general order, for example, explicitly prohibits officers from requesting information or documents to determine immigration status unless required by state or federal law.6Colorado Springs Police Department. General Order 305 – Immigration and Foreign Nationals – Section: .10 Requesting or Collecting Information
Officers also cannot volunteer non-public personal information to federal immigration agents during the course of their work. A workplace, daily schedule, or home address is off-limits unless the request comes with proper legal authority. The reasoning is practical: if immigrant communities fear that calling the police about a burglary or a domestic violence situation could trigger deportation proceedings, crime goes unreported.
Officers who violate these protocols can face internal disciplinary action, and their departments may face liability under state civil rights provisions.
287(g) Agreements Are Effectively Blocked
The federal 287(g) program allows local law enforcement agencies to sign agreements with ICE that delegate limited immigration enforcement authority to local officers. A January 2025 executive order directed ICE to expand the program to the maximum extent permitted by law.7U.S. Immigration and Customs Enforcement. Delegation of Immigration Authority Section 287(g) Immigration and Nationality Act
Colorado is an outlier regionally. At least one Colorado sheriff, in Teller County, attempted to enter into an agreement with ICE and was stopped through legal action. Pitkin County’s 2017 resolution explicitly prohibits county personnel from participating in 287(g), and the statewide statutory framework makes compliance with such an agreement functionally impossible for Colorado agencies. Officers cannot honor detainers, cannot share non-public information, and cannot delay releases, all of which are central to how 287(g) operates.
What Sanctuary Laws Do Not Do
This is where many people get confused. Sanctuary laws limit local cooperation. They do not prevent federal agents from conducting their own operations on their own authority. ICE agents can still arrest people in Colorado. They can conduct operations at apartment complexes, businesses, and public spaces. What they cannot do is use local police, local jails, or local government resources to help them.
In 2025, ICE conducted high-profile operations at apartment buildings in Aurora and Denver in early February and raided a Colorado Springs nightclub in April. Immigration attorneys reported a shift in enforcement patterns: roughly 88% of people detained through their organizations in 2025 were picked up internally, at workplaces, homes, or during traffic stops, compared to less than 10% in 2024.
For residents, the practical takeaway is that sanctuary laws affect the behavior of local government employees, not federal agents. A Denver police officer will not ask about your immigration status during a fender-bender investigation. An ICE agent operating independently can still approach you in a parking lot. Knowing which agency you are dealing with matters, and you have the right to ask.
The Federal Challenge and Funding Pressure
Colorado’s framework is actively contested. Under 8 U.S.C. § 1373, no state or local government entity may prohibit or restrict any government official from sending, receiving, maintaining, or exchanging information about an individual’s citizenship or immigration status with federal immigration authorities.8Office of the Law Revision Counsel. 8 USC 1373 – Communication Between Government Agencies and the Immigration and Naturalization Service A companion provision, 8 U.S.C. § 1644, contains nearly identical language specifically targeting state and local government entities.9Office of the Law Revision Counsel. 8 USC 1644 – Communication Between State and Local Government Agencies and Immigration and Naturalization Service
In 2025, the United States filed a lawsuit challenging HB 19-1124, HB 23-1100, SB 25-276, and Denver’s municipal laws, arguing they were preempted by federal immigration law. In March 2026, a federal district court dismissed all of the government’s claims, finding the federal government failed to state viable claims and that ruling otherwise would conflict with the Tenth Amendment. An appeal is possible.
The other pressure point is money. A January 2025 executive order directed federal officials to evaluate and take lawful actions to ensure that sanctuary jurisdictions do not receive access to federal funds.10The White House. Protecting The American People Against Invasion A follow-up order in April 2025 directed every federal agency head to identify grants and contracts to sanctuary jurisdictions for suspension or termination.11The White House. Protecting American Communities from Criminal Aliens The Department of Justice’s COPS Hiring Program requires applicants to certify compliance with 8 U.S.C. § 1373.12COPS Office. COPS Hiring Program The Byrne Justice Assistance Grant program has similarly imposed conditions requiring jurisdictions to provide federal authorities with release dates of incarcerated undocumented individuals and to allow federal agents access to those individuals in custody. Colorado’s state laws prohibit both, creating a direct eligibility conflict.
Whether federal funds can actually be withheld as leverage remains an open legal question. The threat creates budget uncertainty for counties that rely on federal law enforcement grants, but the core sanctuary rules are still in force in every Colorado county as the litigation continues.