This is something we are going to discuss at the end of the semester, but I wanted to flag it for you now. The United States has entered into a consent decree with the Baltimore Police Department (formally, an injunction, the terms of which the parties negotiated and the court approved), requiring changes in department practices on all manner of issues. The United States brought a civil action against the department pursuant to 42 U.S.C. § 14141, which allows DOJ to sue state and local law-enforcement agencies to stop patterns of unconstitutional conduct. Section 14141 is a new weapon (it was enacted in 1996), an alternative to criminal prosecution under § 242 and civil litigation under § 1983.
The Obama Justice Department used § 14141 extensively; this is one of several similar consent decrees the Department has entered into. One thing to watch is how the Trump/Sessions DOJ uses this provision.
Again, we will talk about this in our Remedies discussion, toward the end of the semester. For now, have a look at the (lengthy) document.