You MUST obey the law, and do your best to get others to do so as well. You are compulsive about it. In an area with little or no law, you will not "go wild" - you will act as though the laws of your own home are in force. This is a disadvantage, because it will often limit your options! Faced with unreasonable laws, you must roll against IQ to see the "need" to break them, or to avoid turning yourself in afterwards! If you ever behave dishonestly, the GM may penalize you for bad role-playing.
You may fight (or even start a fight, if you do it in a legal way). You may even kill in a legal duel, or in self-defense - but you may never murder. You may steal if there is great need, but only as a last resort, and you must attempt to pay your victims back late. If you are jailed for a crime you did not commit, but treated fairly and as-sured of a trial, you will not try to es-cape.
You will always keep you word. (In a war, you may act "dishonestly" against the enemy, but you will not be happy about it!) You will also assume others are honest unless you know otherwise (make an IQ roll to realize someone may be dishonest if you haven't seen proof).
Honesty has its rewards, of course. If you stay alive and in one place long enough for your honest to become known, GMs should allow you a +1 on any non-combat reaction roll, or a +3 if a question of trust or honor is actually involved. This is essentially a free "reputation" reaction bonus.
You are allowed to lie if it does not involve breaking the law. (See Truthfulness)