CHICAGO (CBS) — Chicago is the first city to file a federal lawsuit against attorney general Jeff Sessions regarding a hit against sanctuary cities — and mayor Rahm Emanuel believes others will follow.

The suit claims millions of dollars in federal grants should not be withheld from so-called sanctuary cities.

The federal Byrne grants support local law enforcement, but the 2017 application has some new rules. For one, Sessions will be requiring police stations to give 24-7 access to immigration and customs enforcement.

“By protecting criminals from immigration enforcement, cities and states with so-called ‘sanctuary’ policies make all of us less safe,” Sessions recently said. “We saw that just last week, when an illegal alien who had been deported twenty times and was wanted by immigration authorities allegedly sexually assaulted an elderly woman in Portland, a city that refuses to cooperate with immigration enforcement.”

Corporation counsel, Ed Siskel, says second cities would have to give the feds 48-hours advance notice of an arrestee’s release.

“Which, in many cases, would require detaining individual residents longer than necessary for the sole purpose of providing that 48-hour advance notice — in violation of their fourth amendment rights.”

Chicago Police Supt. Eddie Johnson joined Siskel and Emanuel at a news conference announcing the lawsuit. He said the CPD is “here for you regardless of who you are or where you’re from.”

Emanuel also chimed in on the city’s behalf, saying, “Chicago will not let our police officers become political pawns in a debate. Chicago will not let our residents have their fundamental rights isolated and violated.”

The mayor, with support from other city leaders, also made it clear Chicago will continue to protect illegal immigrants.

The Department of Justice responded by saying, “In 2016, more Chicagoans were murdered than in New York City and Los Angeles combined. So it’s especially tragic that the mayor is less concerned with that staggering figure than he is spending time and taxpayer money protecting criminal aliens and putting Chicago’s law enforcement at greater risk.”

The lawsuit is expected to be filed in federal court first thing Monday morning.

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