Monell v. City of New York Department of Social Services, 436 U.S. 658 (1978) requires that you consider another approach besides the one listed above.
Under Monell, if the police department exhibits a pattern of conduct in which you were involved (racially motivated bias toward you) then a civil rights lawsuit can be plead against the department. Monell v. City of New York Department of Social Services, 436 U.S. 658 (1978) ruled in part that municipalities do in fact qualify as "persons" under Section 1983 of the Civil Rights Act.
Now, to the basics......
The laws that protect citizens against government misconduct are commonly called civil rights laws.
A violation of a clearly established constitutional right under color of law gives rise to a Section 1983 civil rights lawsuit. In this situation, you may have a civil rights violation but you should see a lawyer in your locale to fully discuss your situation. Because you have a conviction, your road to success may be a bit more difficult. However, even convicted persons have civil rights.
You might find my Legal Guide helpful "How to Choose A Lawyer For You"
You might find my Legal Guide helpful " What Do I Tell My Lawyer"
You may find help in my Legal Guide "What is a Civil Right?"
Act quickly because such lawsuits have strict time limits, called statutes of limitations.
Good luck to you.
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