But that's not the penalty that the Edo specified for the crime Wesley committed. When Starfleet sets foot on an alien planet they should be under the laws of that planet. It's not like they were even invited. They simply showed up, beamed down and assumed that things worked the same there as they did in the Federation. The Edo are not human, regardless of appearances. They have their own culture and have the right to employ whatever laws they see fit on their world. The Edo were healthy, happy and apparently quite prosperous. Their system worked for them. By landing on their planet, Starfleet put themselves under the jurisdiction of the Edo. A first contact team is not an embassy. They do not enjoy diplomatic immunity.