I'm kind of torn on the issue. I mean, on one hand if I committed a crime in another country, I would like to have the opportunity to talk to my embassy. "Crime" means different things in different countries, I mean, you can't spit on the sidewalk in Singapore, but an American could easily not know this. I'm not making excuses, just saying that cultures are vastly different and it's impossible to know every single law in a country that you're visiting for two weeks.
But, with that being said, the Mexican government and the UN could've chosen a better candidate for taking up this fight, than a couple of murdering rapists. What a bad decision on their part. How about finding someone whose crime is not so heinous and whose guilt is somewhat questionable?