Medical debts incurred before spouses are married are generally the sole responsibility of the spouse who received the medical care or treatment. Similarly, medical debts incurred after spouses are divorced are generally the sole responsibility of the spouse who received the medical care or treatment. But medical debts incurred during the marriage are generally considered a marital debt and the responsibility of both spouses. In some states, such as Minnesota and Virginia, a spouse is not responsible for the other spouse’s medical debts incurred following separation.

Under the (legal) doctrine of necessities, a spouse is generally liable for debts incurred by the other spouse—even if the spouse was not aware of and did not approve the purchase of the products or services, and even if, for example, the provider of the medical services did not know the spouse receiving the services was married. The doctrine of legal necessities generally makes spouses liable for the life necessities of the other spouse—food, basic clothing, shelter, medical care, and utilities—during the marriage. At least two states—Alabama and Virginia—have declared the doctrine of necessities unconstitutional. And in Maryland, for example, a spouse is only responsible for the other spouse’s medical bills if the spouse agreed in writing to be responsible for the other spouse’s medical bills.

Liability for medical debts incurred during marriage may be joint and several liability—meaning the creditor (medical services provider) may choose to pursue only the spouse who did not receive the medical care for payment of the medical bills. This is generally the case in community property states, and in states that consider medical bills joint debts.

In New Mexico, medical debts incurred before marriage are typically the responsibility of the spouse who received the medical care. Similarly, medical debts after divorce fall on the spouse who incurred them. However, medical debts incurred during the marriage are often considered joint marital debts, for which both spouses may be responsible. New Mexico is not a community property state, but it does follow the doctrine of necessities, which means that one spouse may be liable for necessary expenses, such as medical care, incurred by the other during the marriage. This doctrine holds that spouses are responsible for each other's basic needs, which include medical care. However, the application of this doctrine can vary, and certain defenses may be available to a spouse who is being pursued for the other spouse's medical debts. It's important to note that the specifics of liability can be complex and may be influenced by additional factors such as separation agreements or prenuptial agreements. An attorney can provide advice tailored to an individual's situation.