This petition is anti-productive. You don't need a courtroom if you will just let the majority of uneducated citizens decide their sentence. I think it's awful what they did, but they shouldn't be sentenced differently because they went viral. The jury and court will feel obligated to give them a harsh sentence, to make an example of them for the rest of the world, but this isn't fair to any of the parties involved.
Honestly, what is more important, the fate of the dog that has been taken away, or the fate of the two teenagers?