Mexico's Legal System
There are some big differences in the legal system in Mexico, so you should know the basics.
One of the biggest things to understand about Mexican law compared to the United States is that the U.S. is based on common-law and Mexico is based on Civil Law. Civil law is based on the creation of codes (laws) by legal scholars, and judges and lawyers look to these scholars as the authority on said laws. In Mexico, only legislature can create new laws.
Another big difference is the role of attorneys. In the U.S., attorneys for the plaintiff or defendant do the investigation, examine witnesses, and appoint experts. In Mexico, this is all done by the judge. Mexican attorneys can still council their clients and prepare proceedings.
Whether you are buying a home, getting married, or trying to become a permanent resident in Mexico, it's wise to consult a Mexican attorney for advice.
Of note and consideration - when it comes to committing crimes in Mexico, their system is nowhere near as advanced as that of the United States. In the U.S. almost every crime is documented on a person's record. In Mexico, only very serious crimes (i.e. murder) are documented. Many times, someone could be arrested for breaking and entering, theft, or a number of smaller crimes and after spending a few days in jail, are released with no records filed.