Two games ago Brooks had a nasty helmet to helmet that knocked Whop out for two games. Refs did not see it apparently. Also had a tough one last year vs Scott. I won't speak for the integrity of the guy becuase I know nothing else about him but those were some ugly impacts to the head...particularly Whop.LOL. Brooks had one (marginal) targeting penalty this year. He certainly isn't dirty.
Smith hits hard, but also isn't dirty.
Brisker had a hit on the Nova QB last week that was textbook. Totally clean, no helmet, not late, but lit him up.
IU has played dirty dating back at least to the cheap shot on Mauti's knee.