Where in the article does the OSI mention or hint at anything about threat of law? The OSI does have the legal right to tell you what they think Open Source is. You have the legal right to ignore it. All OSI did is say "here is our definition of Open Source, and these are the people that agree with us, and you should agree with us too."
I wasn't referring to legality, only replying to the idea that "open" and "source" are "just two words". For an example closer to the subject at hand, the Free Software Foundation makes it clear what does and what does not fit the Free Software definition and that does not rely on the force of law.
Bourbon is just a just a name. Champagne is just a region. But whiskeys and wines have to fit narrow qualifications to be Champagne sparkling wine, or Bourbon whiskey. You can, of course, call any software you want open source regardless if it fits the OSI definition, just like you can call any sparkling wine you want Champagne. It doesn't mean you'd be correct in doing so.
http://freakonomics.com/podcast/atul-gawande/