Colorado’s second-highest court ruled on Wednesday that the Teller County sheriff cannot rely on an agreement with the federal government to authorize his deputies to perform immigration duties state law prohibits — specifically, the continued detention of noncitizens beyond their release from custody.

In 2019, the state legislature enacted a law forbidding local law enforcement from honoring civil detainer requests from immigration authorities, including warrants not signed by a judge and issued solely by executive branch employees. However, Sheriff Jason Mikesell contended the prohibition did not apply to an arrangement he entered into with U.S. Immigration and Customs Enforcement.

Known as a 287(g) agreement, some of Mikesell’s employees were authorized to perform the tasks of federal immigration officers, including acting on civil immigration warrants. A trial judge previously agreed with Mikesell that the 287(g) agreement rendered his deputies “de facto” federal immigration officers and permitted the arrangement to continue.

But a three-judge panel for the Court of Appeals noted a problem: The 287(g) agreement permitted Mikesell’s deputies to participate in immigration enforcement “to the extent consistent” with state law. Initiating a detention at the direction of ICE was not consistent with the 2019 change in law.

“Though a procedure that requires ICE officers to directly arrest and detain aliens — rather than delegating such authority to local law enforcement — would require ICE to exercise more effort to apprehend and detain aliens, it was the legislature’s prerogative to require immigration officials to put forth that effort in Colorado,” wrote Judge Pax L. Moultrie in the July 3 opinion.

Six residents of Teller County filed suit against Mikesell, alleging the sheriff was using their tax dollars to carry out the 287(g) program in violation of Colorado law. Then-District Court Judge Scott Sells initially dismissed the case on the belief the plaintiffs lacked standing, but the Court of Appeals reinstated the suit in 2021.

At a January 2023 trial, Sells heard the Teller County Sheriff’s Office has had an agreement since 2000 to detain people on behalf of ICE. Since the 287(g) program began in 2019, four of Mikesell’s deputies were trained to perform certain functions of ICE officers in the county jail, including interrogating detainees, serving ICE warrants and holding detainees on ICE’s behalf for up to 48 hours after they are released from custody on their state charges.

The designated deputies held a total of three detainees at ICE’s request after they had posted bond. The men were all transferred to ICE detention.

Calling the 287(g) arrangement a “modest program,” Sells concluded Colorado law did not prohibit Mikesell from using his employees to carry out federal immigration functions. Specifically, he found the deputies acted as “de facto federal immigration officers” and state law could not “invalidate federal arrest warrants.”

“If Plaintiffs prevail, the consequence would be a system where an inmate walks out of the Jail after posting bond, possibly being met by family members in the Jail parking lot and then being arrested by ICE officials,” Sells wrote. “Plaintiffs give no consideration of how their preferred procedure might affect the safety of the inmate, family, ICE officer, TCSO deputies or the public.”

The plaintiffs turned to the Court of Appeals, noting that nothing prevented Mikesell from communicating with ICE about detainees. But the federal government also required 287(g) arrangements to be consistent with state and local law.

“The sheriff can’t do what Colorado law doesn’t authorize or forbids him from doing,” argued attorney Stephen G. Masciocchi to the appellate panel. “Our constitution and the statute in question forbid him from arresting or detaining persons for civil immigration purposes.”

Teller County Attorney Paul W. Hurcomb countered the detentions of noncitizens were necessarily valid because the civil arrest warrants were valid.

“It’s valid under federal law,” interjected Moultrie. “But isn’t the whole issue plaintiffs argue is that it’s not valid under Colorado law?”

“Do you have to comply with state and local law or not?” added Judge David H. Yun.

Yes, responded Hurcomb, “and our contention is we are complying with state and local law. Colorado law does not prohibit a 287(g) agreement.”

Not so, the Court of Appeals concluded. Moultrie explained the 2019 legislative change explicitly applied to non-judicial immigration arrest warrants, and the 287(g) agreement clearly envisioned local law enforcement agencies would comply with their states’ laws.

“Thus, we disagree with the district court’s conclusion that the (deputies) are federal officers solely accountable to federal law while performing immigration enforcement function,” she wrote.

Attorneys for the plaintiffs and for Mikesell were not immediately available for comment. The plaintiffs noted in their complaint that Mikesell was the only Colorado sheriff to have a 287(g) agreement.

The case is Nash et al. v. Mikesell.