Many states in the southwest that were originally Mexican territory have inherited several unique features from the civil law that governed when they were part of Mexico. These states include Arizona, California, Nevada, New Mexico, and Texas. For example, these states all have a community property system for the property of married persons (Idaho, Washington, and Wisconsin have also adopted community property systems, but they did not inherit them from a previous civil law system that governed the state). Another example of civil law influence in these states can be seen in the California Civil Code, where the law of contracts is treated as part of the law of obligations.