I like the "Aiding and Abetting" idea and many of the ideas. I do not like the "Accomplice" idea as stated. In real life, accomplices to a crime are guilty of the same crime even if they didn't actually "do it." There are even "accomplices after the fact."
These are relatively good ideas in and of themselves but I would rather have the peripheral chars have less trouble than the trouble-makers themselves. This would allow new players to still ease into the PK and law-breaking arena without full impact of the law. This would also allow older players to go PK-lite and law-breaker-lite and take less punishment. We don't need another group of "flashes in the pan" to arise out of this new law, deleting their master level priest because they wandered alone into the wrong place and don't want to wait the duration in jail. This all assumes "Aiding and Abetting" is a lesser crime.
As I said, I do not like the "accomplice" idea as stated. I do like an "accomplice" idea, though. For the purposes of the game, I suggest an accomplice is someone who takes part in the assaulting via melee or magic. This encompasses all group members and anyone outside the group who does any sort of attack in the process. Those in the group of any attackers who did not do any sort of attack would not be accomplices but would be aiding and abetting. Understand this is not the whole of "aiding and abetting" but a separation of "accomplice" and "aiding and abetting."
For definition purposes, I would consider a gate to a target or the summoning of the target as an accomplice act. For further clarification, gating to a target would include gating to anyone in the same room as the target. If you want to be sneaky and walk around with the target and let killers gate to you, the law can't see everything. Don't do anything else and you got away with your accomplice act--unless PCs can tie you to the act within the RP realm of the game.
Other than being a non-combatant within the group of people committing crimes, aiding and abetting would include giving anything to the criminal during commission or after the fact, while within the offended kingdom or any allied kingdom. Giving anything includes, but is not limited to, gear, weapons, coin, tools, beneficial magic, beneficial song.
After-the-fact aiding and abetting should only be reportable by law NPCs, tribunal members (PC) and allies of tribunal members (PC). Also, atf a+a should be a lesser crime than collaborative a+a.
I'm not certain how far off-topic I already went in a couple points, but I would also like to add in the idea of extradition between allies.
1)Nerina and Taslamar are allies.
2)You have committed crimes in Nerina to require 6 days, 12 hours in jail followed by execution.
3)Taslamar catches you and throws you in jail.
4)By extradition treaty (coded into ally status), Taslamar will hold you for 1/6 the time, or 1 day, 2 hours, while awaiting an extradition request. The execution part of the penalty is wholly disregarded in the allied kingdom.
5)Any Talon can approach the Peacekeeper judge to submit extradition papers and complete the extradition.
6)Upon logon, criminal and jail will be transmitted to the Talon member, along with length of time remaining to file papers.
7)Upon extradition, time served in Peacekeeper jail will count as time served in the Talon jail.
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If the entire time awaiting extradition is served without extradition, the Peacekeepers will free you and you will no longer be jailed for those crimes in Taslamar.
9)All time, gear, coin penalties Zhenshi levees will be followed by the 1/6 rule, but execution and maiming penalties will be ignored. So, if Zhenshi only wants to execute you, Taslamar will "capture and release" you, holding their extradition treaty met in this event.
Okay, now that most people have already quit reading my response, I'll let the rest of you quit reading it.