You know, for all my complaining about the Old North State I do not think refs cheat. I think they are biased. Here is the difference for me. A cheater wants to use his influence over the game to get the outcome he desires. He knowingly makes wrong calls to help his favored team win. Very few refs resort to cheating, in my opinion.
Bias occurs whenever the league believes there would be greater benefit to some programs succeeding over others. This kind of bias is shaped by conference offices and media. I think the bias in the ACC is strong. Bias occurs whenever the league believes the U or FSU winning is better for it than BC or Maryland winning. Bias occurs when the conference believes it is a good thing for the conference when UNC is doing well, that the conference woould be better served by getting a North Carolina school in the conference championship, or that it is best for the ACC when Duke and UNC basketball are on top. For instance, the media here always argues that the ACC basketball tournament suffers when North Carolina schools lose. They act as if the league must endure a disaster when there is a GT-UVA final as in '90. Swofford and tobacco road media, assisted far too often by national media, perpetuate a strong bias in the ACC.
I don't see this as much in other conferences. I don't think the Big East cares if it's WVU, Rutgers, or Syracuse on top. I think the SEC has a bias against its lesser knowns - Miss State, Vandy, Ky, in football, and maybe to a lesser extent against newbies Arkansas and SC. But, I don't think there is a bias that says the league is better off having Georgia beat Florida, LSU beat Auburn, or Tennessee beat Alabama.
I think the mentality of the ACC here in North Carolina is that the conference is best served by North Carolina's success, to a lesser exetent NC State, and Duke in basketball. Once that bias is established, it subtlely influences everything from refereeing to scheduling.
I do think the bias is real.