Federal immigration officers struggled to answer basic questions about warrantless arrests and admitted during testimony in federal court in Denver on Tuesday that they had not received training about how to comply with a court order limiting how they can arrest people in Colorado.
Three deportation officers with U.S. Immigration and Customs Enforcement testified that they have continued to arrest people without getting warrants beforehand and without determining whether they pose a flight risk, despite a Nov. 25 court order barring them from doing just that. In some cases, the officers said, they are obtaining “field warrants” from their supervisors after arrests.
The hearing was the latest development in an effort by immigration lawyers in Colorado to push back in court against the Trump administration’s mass deportation policy, which has resulted in a skyrocketing number of arrests and detentions, mostly of people who have no criminal record.
Lawyers for immigrants allege ICE has been violating the court order and officers are continuing to arrest immigrants across Colorado without the correct legal justification or documentation. They are asking U.S. District Judge R. Brooke Jackson to intervene.
“The relief can’t wait,” said Anna Kurtz, a lawyer with the American Civil Liberties Union of Colorado. “Every violation causes profound harm to human beings that can’t be undone.”
Jackson, who was nominated to the federal bench by President Barack Obama in 2011, allowed the ICE officers to testify using only their initials, granting a request from the lawyers for the Trump administration. Jackson said he received a threat after he issued the preliminary injunction in November and wanted to protect the safety of everyone involved in the case. Someone in Florida published Jackson’s home address and encouraged immigrants to move to his house, he said.
“Even though I am in a position of believing very strongly that these are public matters,” Jackson said, “when it comes to the safety of people who appear in court, I am going to do what I can to protect them.”
Gregory Davies, the assistant field office director for ICE in Denver, said the Denver office has hired dozens of new officers recently and is making about 15 to 25 arrests per day even as training hours have been cut. He said four officers were removed from the field recently in part due to their failure to correctly document arrests.
Davies also said officers involved in the case of threatening ace of spades cards left in the vehicles of men detained in Eagle County in January are “no longer involved in the field” while an investigation continues. He did not say how many officers were involved in the incident.
Throughout the hearing, lawyers for the Trump administration said ICE is making progress but needs more time to comply with Jackson’s order. The judge appeared skeptical of that argument.
“We’ve got 60 or 120 new officers flooding in, making up to 25 arrests of people a day,” Jackson said. “It’s an extraordinary thing that’s happening in this country, including in this state. It’s an unprecedented thing. I can’t just assume that all these guys are getting trained or getting it when we have yet to see one (arrest document) that was filled out properly for a warrantless arrest.”
Jackson questioned the ICE officers’ practice of getting field warrants from their supervisors after arrests.
“You can’t take them into headquarters and then paper it with a warrant,” he said. “That’s not compliance.”
More warrantless arrests
Testimony and arrest records reviewed during the hearing show that even after the Nov. 25 order, ICE officers arrested people who were not their targets and about whom they had no information. Information the court ordered officers to put in the arrest reports was missing, including whether the agents had a warrant, the person’s ties to the community and reasons they are a flight risk.
Dionisio Castillo, 53, tearfully recalled how two ICE agents arrested him at his construction job site in January without asking him any personal questions. Had they asked, they would have known he has lived undocumented in the U.S. for 30 years, has three U.S. citizen children and no criminal history. He spent 48 days at the ICE detention facility in Aurora. His family had to pay a $2,500 bond for his release.
“I was standing next to my truck and I turned to the right and I saw that the officers were walking toward me,” said Castillo through an interpreter. “They handcuffed me with my hands behind my back.”
Officers testified they got a field warrant for Castillo after the arrest.
Jackson called the arrest “improper.”
“He certainly wasn’t targeted,” Jackson said. “That’s the case we’re trying to prevent here. You guys (Trump administration lawyers) should be on our team on that. We should all be in agreement that that is improper.”
Difficulty answering questions
The three ICE deportation officers, including those who made Castillo’s arrest, struggled to describe the evidence of flight risk that, when making a warrantless arrest, must be documented after asking about someone’s ties to the community.
One officer who identified himself by the initials J.B., recalled arresting someone immediately after determining they were undocumented.
“As soon as they claimed they’re in the U.S. illegally, I arrested them,” J.B. said of a Dec. 27 case. “If you ask more questions the likelihood of them trying to escape increases.”
J.B. said ICE hired him in 2020 and he has regularly received training on warrantless arrest protocol. In October, ICE sent J.B. to Oregon for about 28 days as part of a surge of immigration enforcement there, he said. J.B. has testified in federal court in Oregon in a lawsuit brought by immigrants as a result of that surge, he said.
In Oregon on Oct. 30, J.B. said he made the decision to pull over a white van with seven people inside. Almost immediately, he smashed the driver’s side window, according to the federal judge in the Oregon case who reviewed video of the arrest. J.B. destroyed records related to the operation, which he told the Denver judge was not intentional.
The federal judge in Oregon issued a similar preliminary injunction about warrantless arrests there last month. In his order, he said the evidence shows “ICE’s practice of fabricating warrants after arrests were made.”
An officer with the initials J.L. repeatedly paused for about 20 seconds after being asked questions about his understanding of the court’s order and the process for arresting people without warrants.
Jackson voiced frustration with the officers’ testimony.
“They didn’t have a clue,” he said, interrupting Nick Deuschle, a lawyer for the Trump administration, during his closing arguments. “They didn’t know about the policy pronouncements that have been issued by ICE, they hadn’t received any serious training, they didn’t have the ability to answer … questions.”
ICE has removed J.B. and J.L. from the field, according Deuschle. He did not say why the officers were removed.
Deuschle said the evidence “does not demonstrate willful widespread noncompliance with the court’s order.” He said the remedies the lawyers for the immigrants are seeking, including prohibiting untrained ICE officers from making arrests, “aren’t necessary.”
Jackson appeared to disagree.
“Why would we want these guys to go out to make arrests if they haven’t been trained properly?” he said. “Take them out of the field or not, they were supposed to be trained. … Those guys were not examples of what we hope ICE officers would know and do in the field.”
Conflicting directives from ICE leadership
Davies, the third in command at ICE’s Denver field office, which handles arrests in Colorado and Wyoming, said there have been at least four leaders of the office since President Donald Trump’s inauguration in January 2025.
After the court’s November preliminary injunction, Davies said he trained about 15 ICE officers in charge of processing arrests on how to comply with the order.
But messages from ICE leadership have provided conflicting information.
In a Jan. 16 post on the social media site X, the Department of Homeland Security wrote: “Law enforcement uses ‘reasonable suspicion’ to make arrests, as protected under the Fourth Amendment to the U.S. Constitution.”
The Fourth Amendment requires “probable cause” for arrests, not “reasonable suspicion.” Probable cause is a higher standard that requires more concrete evidence.
“My officers know that probable cause is the standard in Denver,” Davies said.
Davies said ICE headquarters has verbally told someone in the Denver field office recently to return to conducting targeted arrests with warrants instead of arresting mostly “collaterals,” or people officers encounter on the street without any prior information about them.
Lawyers from the American Civil Liberties Union of Colorado, the Meyer Law Office and Olson Grimsley Kawanabe Hinchcliff & Murray LLC sued the Trump administration in October with four original plaintiffs who had all been arrested and detained by immigration agents in Colorado.
One of the plaintiffs is Caroline Dias Goncalves, a 19-year-old University of Utah student who was brought to the U.S. as a child. She was arrested by ICE in June, after a Mesa County sheriff’s deputy pulled her over in Fruita and asked about her accent and immigration status. She spent 15 days in ICE’s Aurora detention center and paid $2,000 for her bond, according to the ACLU.
In their amended complaint alleging ICE is violating the court’s order, the lawyers added as a plaintiff the East Colfax Community Collective, a Denver-based organization that helps people and small businesses avoid eviction. ICE has arrested at least three members of the organization at their apartments, all asylum seekers originally from countries in Africa.
The number of immigration arrests in Colorado has shot up since Trump took office more than a year ago.
ICE arrested at least 3,522 people in Colorado between Jan. 20, 2025, and Oct. 15, 2025, according to the most recent data obtained from ICE and published by the University of California, Berkeley, School of Law’s Deportation Data Project, up from 843 during the same period in 2024.
Most of those arrested by ICE in Colorado did not have prior criminal convictions, according to the data.
By comparison, 37% of those arrested by immigration agents in Colorado between Jan. 20, 2025, and Oct. 15, 2025, had prior criminal convictions, down from 61% in 2024.