The below statement can be attributed to Colleen Connell, Executive Director, ACLU of Illinois:

“In recent days, the Trump Administration has threatened to send unmarked federal forces to Chicago and other cities across the country. Given the documented abuse in Portland by federal forces against the press and those protesting police killing of Black people, it is clear that we are in a fight to save our democracy against a reckless administration bent on terrorizing our communities and endangering lives.
Make no mistake: Trump’s federal troops will not be a constructive force in Chicago. As our colleagues have seen in Portland, Trump’s secret forces will terrorize communities and create chaos. This is not law and order. This is an assault on the people of this country, and the specific protections of protest and press in the First Amendment.
The ACLU opposes the deployment of federal forces in Chicago by the Trump Administration. We will hold the Trump Administration and any such federal forces accountable for unconstitutional actions.”