BTW, I have no problem with the league having a policy against players/coaches criticizing refs. I think that is bad for the league as a whole, and they should protect that. The complaints should be kept in-house, and dealt with through formal complaints to the league office.
With that said, the league also needs to realize that it has a very real problem right now, where the fans think the refs are biased. The only way to fix that is to be much more transparent about what they are doing to fix it. And honestly, they don't even need to DO anything, to fix the public-relations problem, they just need to put on a dog and pony show, like MLB did with the steroids investigation. The fact that their response is always "we deal with it internally, and review everything...no, you cannot have any details" is that kills them, and promotes the thinking that THEY are the ones fixing games.