The policy in question refers to what are known as "48-hour ICE detainer requests."
Last July, Louisville Mayor Craig Greenberg, a Democrat, agreed to reinstate a 48-hour hold for "inmates who are arrested for crimes, are booked in our jail, and are subject to deportation notices" to grant federal immigration officers the time to take the inmates into custody.
Following the deadly immigration crackdown in Minnesota, Greenberg defended the more cooperative approach with the Trump administration.
"This decision, while nobody likes it, including myself... I still believe we're protecting the most number of immigrants in this community," he said.
But the ACLU has warned of multiple issues, from deaths at the jail, to overcrowding, to aiding in aggressive ICE operations.
"On the day it was announced, the Trump administration declared victory in Louisville and threatened other municipalities to follow Louisville's lead," an ACLU spokesperson said in a video post. "And if they didn't, they threatened that they would face lawsuits or the potential loss of federal funding."
In the group's new analysis, to be released Thursday, the civil rights group says there has been a "significant shift" in ICE detainer activity following the policy change. The report also "examines how Louisville's jail has increasingly become a pathway into federal immigration detention."
The ACLU is urging Greenberg to reverse the policy.