None. America has a lot of barriers to keep certain people from the franchise, and all mainstream media is lies and ads. But America is the only place where the concept of truly free speech is even held up as a virtue, let alone accorded the people in practice.

Tough to say. I suppose you need an intersection of high voter turnout, low scores on corruption indexes and laws that prevent companies from donating or having too much sway over individual representation. All of the above is rare, I figure, but not ideally impossible. The phrase "money talks," comes to mind...