These rights are privately enforced. There is no public federal enforcement. You have to do what this gentleman is doing. Sue in the courts.
It is becoming apparent that the U.S. needs an independent agency focussed on transgressions by law enforcement / a civil rights enforcement bureau. One could keep it purely civil, to avoid conflicting with the DoJ. But in the same way that criminal prosecution is specialized enough that consolidating it in the DoJ makes sense, investigating law enforcement is specialized and conflicted enough that consolidating it under an independent agency makes sense.