I'm sorry, what? Anyone born in the US is a citizen, not an immigrant. Their parents may be citizens or immigrants (legal or otherwise).
Section 1 of the 14th amendment: All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.
If you're saying law enforcement agencies are depriving US citizens of liberty without due process I'm sure every news agency in the country would love to run stories with your evidence.