There is no legal procedure or hidden bylaw whereby that the NBA could simply stiff Sterling of a billion dollars. It's not possible, and I challenge you to find any source that suggests otherwise and post it here. You must've misheard. The league was able to consider contraction for the Hornets, but only because the league already owned the franchise after paying out George Shinn. And in that case, Shinn couldn't even make payroll, yet he still got fair market value for his franchise. A vote of an association's membership cannot simply remove a legal asset from another member without fair compensation. Sterling will get paid his franchise's value literally no matter what he tries to do (unless he racked up a billion dollars in fines, I suppose). No association bylaw could trump the basic sanctimony of property embedded in our legal system. Rules can be agreed up to establish and govern membership, but if you take something from someone under one of those rules, you have to pay fair compensation for it. There's no other option.
Courts don't levy injunctions against voluntary associations that treat their punishment decrees as arbitration rulings, like the NBA does. Lester Munson covered that in his last point here:
http://espn.go.com/espn/otl/story/_/id/10852199/challenge-donald-sterling
Adam Silver is a lawyer, and he got the job he currently holds by being an expert on the rules governing the NBA, associations of this nature, their internal mechanisms, labor relations, etc. Sterling will now be searching for a lawyer with half the expertise that Silver already holds in this area of law. Silver is not fucking scared of Donald Sterling's legal expertise. He's pretty sharp on these matters, and I wouldn't bet on him having not fully covered his bases. Ryan Braun stayed on the field by way of the agreed-upon appeal mechanism baseball had in place regarding PED suspensions. For Sterling, there is no appeal process, by agreement of the ownership--that expressly stated in the governing documents (see that Munson article again). That's why it's different. He has no recourse, and agreed to that rule. No one is going to relieve him of the dictates of his own agreement.