Is it possible to reject an inheritance if unknown debts appear after having accepted it?

When an inheritance is accepted, it is accepted with all the consequences. That is to say, If the deceased person had debts, his heirs must take care of them, not being able to exclude them from the acceptance of the inherited estate. In fact, the existence of debts and debits is one of the reasons for ending up rejecting the relevant inheritance, also including Inheritance Tax, among other reasons.
The law is very clear in this regard. The Civil Code indicates that “the acceptance and repudiation of the inheritance, once made, They are irrevocable and cannot be challenged.“. If we decide, then, to accept the inheritance with its assets and its debts, then we will not be able to back down.
But what happens if, once the provisions of the will are accepted, debts appear that had not been known until then? This is one of the great doubts surrounding the possibility of accepting or rejecting an inheritance. It is true that the Civil Code establishes, in the same article as the previous one, that there is the possibility of revoking the acceptance or rejection of an inheritance if “suffer from some of the vices that annul the consent or an unknown will appear”.
Of course, now the question arises what is considered a vice capable of annulling consent, while the reference to the unknown will is clear. A Supreme Court ruling from March 2021 clarifies the situation and what to do in the event that debts appear after having accepted the inheritance.
A sentence of the Supreme to argue the nullity
To enter into context, the affected person who initiated the legal proceedings had accepted an inheritance according to the will. Subsequently, a document appeared in which the cause of the willthat is, the deceased person, recognized for the benefit of some political nephews the right to collect a certain amount of money for the value of some farms.
This debt, contracted by the deceased and which had passed into the hands of his heir, did not appear in the records of last wills and it was a private document, which generated a situation of total ignorance for the person affected by this case, who refuses to pay when the debt is claimed.
The Supreme Court understood that the affected party had accepted the inheritance, at the time, with limited information, since the debt contracted by the deceased was not included and he did not have any way to find out about it. The situation forced him to respond to the debt with his own assets. So, argued that the heir had accepted the debt “by an excusable, essential and determining error”the Court understood that this defect was sufficient reason to reject the acceptance of the inheritance.
Term to cancel the acceptance of an inheritance
If, for example, the existing debt could have been known, like a mortgage, this argument would not have been valid. Thus, the Supreme Court gives a basis to justify in future similar cases to achieve the nullity or invalidity of the acceptance of the inheritance.
It is important to know that the term for the expiration of the nullity action of the acceptance of an inheritance is 4 years and the fact that the Supreme Court considers that the term begins to count from the time the sentence that determines the estate is issued.