Well, I was exaggerating.
I am not a lawyer, but I'd bet it violates current trade, antitrust, or commerce laws if Verizon is purposely trying to keep HTC sales low and Motorola sales high by refusing to distribute nor load new operating systems for HTC phones provided by HTC. Same goes for instructing salespeople to only sell an HTC phone when the customer won't buy a Motorola phone. However, I think it will fall on HTC to file claims and lawsuits that it lost sales and profits due to Verizon violating antitrust laws.
But, what do I know about legal matters?
We own the best phone, but Verizon discriminates against it to keep its sales low. Who, today, would buy a phone with Gingerbread loaded on it?
Remember what happened to Microsoft for favoring its own web browser over others like Mozilla Netscape (firefox)? And these web browsers were all free software. Not an exact comparison, but if Verizon is taking actions to keep HTC sales down, favoring Motorola, I don't think it will take new laws nor a new government agency to be created to investigate and determine what is wrong.