When You Die in Mexico . . .
USA Consular Agent P. J. Maher advises the necessary steps to take when a friend or relative dies. Only a doctor, the Ministerio Público or the Red Cross can declare a person dead. So the first thing to do is to call one of the above.
If the decedent was not under a doctor's care, an autopsy is required. After that, the body can be released to the executor, next of kin, or the Consular Agency and the undertaker. The undertaker will obtain a death certificate (Acta de Defunción) and proceed to treat the body in accordance with the wishes of the deceased or family.
A copy of a birth certificate or passport and the Mexican death certificate, as well as the decedent's social security number will be needed to prepare a "Report of Death of an American Citizen Abroad." This document is legally sufficient for all estate purposes in the USA. If the decedent was a member of the Twenty-four Hour Association, that organization will you through all of the details.
If there is a Last Will and Testament or a Trust Agreement, it is the Executor's/Trustee's responsibility to comply with the wishes of the decedent. You can expect that this process will take one to two years. It would be well to make provisions in your will or trust or in some other manner for cash to tide over the beneficiary during this difficult period.
If the decedent is without a will, that is, intestate, find a good lawyer. Different jurisdictions have different laws governing this situation.