Sterling's angle will be to question the legitimacy of forcing the sale based on the language in the NBA Constitution. He's obligated as a franchisee to follow the league Constitution, but the section allowing dissolving/forcing the sale of a franchise doesn't seem to fit these circumstances well at all.
Thanks for the reply!
Does the US Constitution trump the NBA Constitution?
Of course, but the Bill of Rights refers to what Congress can't restrict (and later, what state governments can't restrict). Private organizations have always had much broader leeway, and free speech has never meant you can't be penalized by those organizations for what you say (again, with rare exceptions like religious/political beliefs). There's no real US Constitution argument here.
Put another way, you or I certainly could and probably would be fired if we were taped saying racist stuff and it came out and embarrassed our employers. I have a cousin who was fired for just saying mildly negative things about work on Facebook. Free speech means we can't go to jail over it or anything like that, but we could definitely lose our jobs. Sterling's a little different as a franchise owner, but the basic principle is similar.