The threat came today, April 12, when the president tweeted that he's strongly considering "placing Illegal Immigrants in Sanctuary Cities only."
If Trump's threat were to come to fruition, Denver would certainly be considered a sanctuary city, even though the city doesn't actually call itself one. The city prohibits local law enforcement from working with federal immigration agents who want to detain individuals after they're set to be released, known as detainer requests.
"I wouldn’t think the Feds would rely on whether a city self-identifies as sanctuary. The Feds accuse Denver of being a sanctuary city and did so when Denver merely refused to hold people on detainers," Mark Silverstein, legal director at the ACLU of Colorado, wrote in an email.
Denver Mayor Michael Hancock was quick to push back against Trump's tweet.
"We need to separate fact from the President’s fiction. We are talking about human beings, not pawns in some political game. These migrants are fleeing violence in their homeland and they deserve our support. Protecting all our residents, regardless of immigration status and within the bounds of federal law is simply what we do as Americans. This is not a time to be partisan, it is a time for compassionate leadership," Hancock said in a statement.
Trump's Twitter tirade follows an April 11 article by the Washington Post that revealed the White House has wanted immigration authorities to release immigration detainees onto the streets of so-called sanctuary cities to retaliate against political opponents.
"Trump administration officials have proposed transporting detained immigrants to sanctuary cities at least twice in the past six months — once in November, as a migrant caravan approached the U.S. southern border, and again in February, amid a standoff with Democrats over funding for Trump’s border wall," the article notes.
Although Hancock doesn't describe Denver as a "sanctuary," the city has taken steps in recent years to bolster protections for its undocumented-immigrant population. In August 2017, city council passed an ordinance that prohibited most city employees from communicating with Immigration and Customs Enforcement or collecting information about an individual's immigration status. It also codified the city policy of not obliging detainer requests from ICE.
Still, the Denver Sheriff's Department continues to notify ICE when a detainee will be released, if ICE puts in such a request. In 2018, ICE sent, and the sheriff's department answered, 108 of these requests, according to the ACLU of Colorado.
In January 2018, then-U.S. Attorney General Jeff Sessions sent letters to 23 jurisdictions, including Denver, threatening to subpoena documents proving they're following legal requirements for cooperating with ICE.
Hancock issued a statement not long after receiving the letter saying that Denver complies with all federal laws and wouldn't be pushed around by the current administration. "Denver won’t back down. We are joined by dozens of other communities, resolute in opposing chaotic and poorly reasoned overreach by Attorney General Sessions, and we will not stand down from doing what is right," he said.
Colorado is in a legal fight with the Trump administration, which is withholding federal grant money because of the state's lack of cooperation with ICE. Attorney General Phil Weiser filed a lawsuit on March 12, demanding that the Department of Justice continue to provide the grant money for law enforcement in Colorado.
There's also a bill working its way through the state legislature that would significantly limit cooperation between local law enforcement agencies and ICE.