Garfield County Sheriff’s Office served cease-and-desist letter for allegedly assisting ICE

A Denver-based nonprofit law firm served Sheriff Lou Vallario and the Garfield County Sheriff’s Office with a cease-and-desist letter Wednesday alleging illegal assistance to federal immigration authorities, according to a Thursday news release from Towards Justice.

The letter outlines several alleged violations of Colorado law related to the Garfield County Sheriff’s Office (GCSO) collaborations with U.S. Immigrations and Custom Enforcement (ICE) authorities at the Garfield County Jail and the creation and operation of the county’s Special Problems Enforcement and Response (SPEAR) task force.

Colorado law limits the extent to which state and local law enforcement officers can work with ICE. Under H.B. 19-1124, officers cannot arrest or detain anyone based solely on a civil immigration detainer, which is not a federal warrant. 

According to ICE’s website, immigration detainers are issued to law enforcement agencies to request that the agency notify ICE “as early as possible before they release a removable alien,” or “hold the alien for up to 48 hours beyond the time they would ordinarily release them,” so they can be transferred to the custody of the Department of Homeland Security, which oversees ICE. 

Under S.B. 25-276, jail custodians are required to release a defendant within six hours after they are granted a recognizance bond or are prepared to post bond. The law prohibits delaying a defendant’s release for an immigration enforcement operation in Colorado.

The statute also states that “a state agency employee or political subdivision employee” cannot share or make accessible personal identifying information — including name, date of birth and citizenship status — that is not publicly available to assist, cooperate or participate in federal immigration enforcement unless required by a court-issued warrant, subpoena or order. It bars detention facility employees from allowing federal immigration authorities access to a part of the facility that is not publicly accessible unless required by a federal warrant. 

In an email with the subject “Immigration Bill” sent to deputies by Vallario on March 4, 2025 — which is included in Towards Justice’s cease-and-desist letter — the sheriff appears to criticize S.B. 25-276, which was passed in May 2025 and co-sponsored by State Rep. Elizabeth Velasco. 

“I have never refused to enforce a law, but I will not comply with this, if this draft is the end result,” Vallario wrote in the email. “You can call me ‘Defendant’ in a lawsuit to correct this pro-criminal stupidity,” he added. 

Towards Justice specifically references the case of Luis Armando Rivas Martinez, which the law firm states is “one of the clearest and most thoroughly documented cases of GCSO and SPEAR assisting civil immigration enforcement.”

According to a SPEAR case report attached to the letter, Task Force Officer Nathan LaGiglia assisted a Homeland Security Investigations (HSI) agent in apprehending Rivas Martinez outside the Glenwood Springs Walmart on June 3, 2025. HSI is a branch within ICE that “conducts federal criminal investigations into the illegal movement of people, goods, money, contraband, weapons and sensitive technology into, out of and through the United States,” according to the HSI website. 

LaGiglia then helped Carter transport Rivas Martinez to a Maverik gas station in De Beque — a 57 mile trip — to meet with ICE Enforcement and Removal Operations (ERO), the case report states. 

“That evening Mr. Rivas was detained at the Aurora ICE Processing Center where he remained for three months before being deported,” the Towards Justice letter states. “During his time in ICE custody, Mr. Rivas was never questioned by federal investigators regarding any federal criminal charge.” 

Rivas Martinez’s case is also referenced by advocacy organization Voces Unidas in a Feb. 9 article outlining 10 alleged civil rights complaints involving the Garfield County Sheriff’s Office within the last year. The organization has reported these cases to Colorado Attorney General Phil Weiser. 

A nine-second video included in the article appears to show Rivas Martinez being detained by two officials: one in a Garfield County deputy uniform and the other in a black shirt with “SPEAR” emblazoned across the back.

Towards Justice also alleges that SPEAR was created in violation of Colorado law. The firm states that the task force was created using a July 2025 Memorandum of Understanding (MOU) that was not approved by a municipal government — an alleged violation of Colorado Revised Statutes (C.R.S.) 29-1-203. However, SPEAR was actually formed in 2022, according to the Garfield County Sheriff’s Office website. SPEAR’s mission is to focus on “drugs, human trafficking, auto thefts, burglaries; robberies, etc.”, and replaced TRIDENT, a similar task force formed in 1994 that focused on drug-related crime.

The letter states that SPEAR creates a “pipeline through which local law enforcement data, including non-public PII (personal identifiable information), is rapidly consolidated and accessible to HSI.”

Towards Justice also includes emails Vallario sent referring to Velasco as a “POS,” stating that his comments display “an astonishing disrespect for public officials advocating for stronger protections for immigrant communities.”

The firm is demanding that the Garfield County Sheriff’s Office stop assisting federal immigration enforcement through methods including detainer-based holds, custody transfers and allowing ICE access to non-public personal identifying information, as well as restricted areas within the jail.

The Post Independent reached out to the Garfield County Sheriff’s Office, Vallario and Towards Justice for comment but did not hear back before the time of publication.

Original reporting from PostIndpendent.com