Editing The Gift:The World (section)

=The Peace=

If a house is included in the Peace, then no other tradition in the Peace may declare war on it.  Anyone who kills or otherwise grossly wrongs a mage from such an tradition might be considered to have breached the Peace by providing a pretext for mage war. Standing in the way of mage war is the Council's most important duty and mages in general are committed to the Peace being kept.  There are many magical groups outside the Peace, but they tend to be smaller and less prominent than the houses within it.  Members of houses from the Peace may be found all over New Spain, whereas other magical groups are usually concentrated in a smaller areas for protection.
Mage society in general and the Council in particular will not tolerate breaches of the Peace or threats to the secrecy of mage society. On the other hand, if you murder an innocent mortal that may or may not cause problems for you. Technically, it is none of the Council's business, but individual members or houses may be appalled and take action, especially if it is a matter of "policing our own". Some houses care more than others. In particular, the Old Houses have a tradition of being tolerant of abuse of mortals, while the Young Houses are more likely to be bothered by ethical concerns.  However, even if the Council does not intervene, that doesn't mean that you got away with it. Your own magical tradition may intervene if they feel shamed by your actions or the neighboring mages may just murder you in disgust. A lot depends on the specific attitudes of your magical tradition and neighbors.