I think there may have been some actual issues with the referees at the Michigan and NW game last night. I am not saying "ZOMG! They had money on the game", but something wasn't right for a Big Ten crew.
Michigan got a lot of penalties the first half. Holding was popular. In the meantime, NW was allowed to flat out hold big as life every fourth offensive play, with probable holds every other play, for the entire first half. Never a call.
Then the scoreboard was started late on the final play of the first half to give NW a better chance of running the score up, with the referee team reviewing what happened and rewarding NW.
The second half we had the helmet loss issue with the play being allowed to continue--I will say that they did punish NW for their coach's poor behavior, both were in MIchigan's favor. Countering that was the way that they would delay whistles when Michigan stars started getting gang piled with three or four defenders.
In Michigan's favor was also the interception review that could have gone either way.
Taken as a whole, there were some fairly serious issues. If the game had stopped at the half I may have been suggesting some sort of bias. As it is with the second half added in, I suspect very poor refereeing--which is almost as bad.