A coalition of advocacy groups, community members, and several district attorneys rallied outside the Colorado Capitol on Thursday to oppose a ballot measure that, if approved by voters in November, would require state and local law enforcement to cooperate with federal immigration authorities.

Backed by the interest group Advance Colorado, Proposition 81 would require law enforcement to notify Immigration and Customs Enforcement when they charge a person who is in the country illegally with a violent crime or when the individual has previously been charged with a felony. This also applies when the person’s legal status cannot be determined.

Kristi Burton Brown, executive vice president of Advance Colorado, told Colorado Politics that the group is pursuing the measure because state law currently bars law enforcement from proactively reporting violent offenders or repeat felons to the Department of Homeland Security. She said a recent state law allows the state to fine an officer up to $50,000 for choosing to report a violent offender to protect the community. She also noted that other sanctuary states, including California and New York, include exceptions in these situations that Colorado does not.

While some have characterized Colorado as a “sanctuary state,” Gov. Jared Polis has pushed back on the label, saying the state “fully cooperates with federal authorities in identifying, apprehending, and prosecuting criminals – regardless of immigration status.”

Speaking from the Capitol steps Thursday, ACLU Colorado director Olivia Mendoza said approving the ballot measure would make communities less safe, particularly under the current administration.

“We have seen that since the beginning of the Trump administration’s second term, our communities have been gripped by the fear of ICE’s brutal immigration enforcement, from warrantless arrests to physical brutality to deplorable detention conditions,” she said. “ICE has no place in our state, and Amendment 81 invites them to take a strong foothold in Colorado.”

Mendoza argued that Proposition 81 violates the Due Process Clause of the Constitution, which prohibits the government from taking away an individual’s life, liberty, or property without fair legal proceedings.

Burton Brown argued that the allegations that the measure violates due process are unfounded because law enforcement would be allowed to report to ICE only after obtaining enough evidence to charge someone with a crime.

According to Denver District Attorney John Walsh, if the measure passed, it would require law enforcement to contact ICE every time they charge someone who has a prior criminal record, unless that person happened to have proof of citizenship with them in the form of a birth certificate or passport.

Walsh called Proposition 81 a “recipe for abuse,” saying it would inevitably lead to racial profiling and the detainment of legal citizens.

“To make things much worse, this obligation triggers on charging a person with a crime, not on a conviction,” he added.

Burton Brown disagreed, noting that nothing in this Proposition 81 allows profiling or gives ICE any authority they don’t have in Colorado.

She added, “Instead, this gives Colorado law enforcement the ability to report violent criminals or repeat felons if they are here illegally without facing a $50,000 fine from the state.”

Proposition 81 would further erode the already strained relationship between immigrant communities and law enforcement, said Walsh.

“Today, state and local law enforcement in this state can truthfully tell the victims and witnesses to a crime that we do not participate in federal civil immigration enforcement,” he said. “If Proposition 81 passes, we would no longer be able to do that.”

Larimer and Jackson County District Attorney Gordon McLaughlin also attended the rally.