Standing before police chiefs from several American cities Feb. 8, President Donald Trump encouraged "turning in the bad ones"—undocumented immigrants who are gang members.
"You have that power," Trump said. "The federal government can never be that precise."
It's a power police agencies already use. Between Jan. 1, 2016, and Jan. 31, 2017, there were 89 inmates held in Ada County Jail at the request of Immigration and Customs Enforcement based on immigration status. They were kept on "detainer requests." When suspects are booked into Ada County Jail, they are fingerprinted and cross-referenced with national databases for outstanding warrants in other jurisdictions. If a suspect is undocumented, ICE may issue a detainer request to keep a suspect until ICE can take custody.
Detainer requests are at the center of controversies over "sanctuary cities," cities where law enforcement doesn't comply with ICE requests to collect information on undocumented people or hand them over to immigration authorities when they're arrested on unrelated charges. Numerous courts have held that being an undocumented immigrant in the U.S. is a civil, rather than criminal, violation, and police cooperation with detainer requests is voluntary.
Pursuing sanctuary status is risky political business, however. Cities that do not comply with federal immigration authorities could lose some funding through federal grant programs, and such policies could alienate voters.
In spite of the risks, some cities deny all detainer requests. Others base compliance on whether the inmate has prior felony convictions, is a gang member or appears on a terrorist watchlist. Ada County Sheriff's Office policy is to accept requests, holding suspects until their state charge has been resolved and then handing them over to ICE. It is not ACSO policy to arrest undocumented foreign nationals.
The Boise City Council voted Jan. 31 to issue a resolution reaffirming the city's commitment to being immigrant friendly. It deliberately fell short of a declaration of sanctuary for undocumented immigrants, but there is demand for this kind of action: According to a Boise Weekly opinion poll, 63.46 percent of 1,382 respondents said they think Boise should become a sanctuary city.