The lawsuit was filed on behalf of Kelvin Francisco Rodriguez, who spent five days in the ICU after being arrested.
The lawsuit alleges law enforcement violated protesters' constitutional rights during the unrest following the killing of George Floyd.
The lawsuit says police pepper-sprayed and threatened journalists, among other things.
A black person is 5.37 times more likely to be arrested than a white person for marijuana possession in Minnesota.
The immigrants were detained even after they had earned their release.
The plaintiff in a case is a rehabilitation ex-felon who is on probation for 40 years.
The ACLU says the victim required five days of intensive care.