I don't see where the Feds have a case, they are not the injured party. The employee got paid. Was the guy a dick? Yep, is there a law against that? Nope.
I agree. The charge that the former employee was discriminated against by being paid in pennies as retribution? Good luck making that stick. The failure to pay OT? Now that's something different but totally unrelated to the pennies.
Right. However, this is something that very likely could've been handled easily and quietly had the DA not made a huge production out of it. "Look at me, I paid a guy in pennies and badmouthed him because he dared to complain!" Knowing that the Feds had already had a complaint filed, Mr. DA should've paid up, called his attorney, and let this play out. If you give someone a reason to come after you, you'd better not turn around, because they're coming.