You could cite that case in Texas where minorities are being stopped by police in some towns and having their cash confiscated by police in accordance with a proceeds of crime law there.
Where I live, there was an incident of 4 cops arresting some guy, and a passing photographer took some pictures - which one of the cops demanded he erase; something the cop had no right to do. This happened Sunday. This could be construed as tampering with evidence if the arrestee decides to contend that his detention was illegal.
There was a story on CNN earlier today where a cop at a drive thru fast-food restaurant (I think it was a McDonald's) drew his gun because the service was too slow. (Illegal use of a firearm, or equivalent).
How about that little old lady a few weeks back that got tasered by that big trooper, it was all over the news. (Excessive use of force.)
Those are the only ones that I can think of at the moment, but I'm sure you Google some more.
Hope this helped.
PS... Idk if there is more police misbehaviour, or that people are more likely to report it, but police officers are given a great deal of power, and a small minority are inclined to misuse it. It really burns my a** when I hear about it.
Forgot, a few years ago there was a big investigation into rampant police corruption in New Orleans, (long before Katrina). Try that.