Short answer. It is a ground for disciplinary action against the lawyer. Counsel has a duty to inform the court within thirty days after the death and to give the name and address of the legal representative, and failure to comply is expressly made disciplinable.
What the law says
it shall be the duty of his counsel to inform the court within thirty days after such death of the fact thereof, and to give the name and address of his legal representative or representatives. Failure of counsel to comply with this duty shall be a ground for disciplinary action.
Rule 3, Section 16 — Death of party; duty of counsel. Read the full provision →
The duty belongs to counsel, and it is specific
Where a party to a pending action dies and the claim is not thereby extinguished, the duty to tell the court belongs to that party's counsel. It has two parts and a deadline. Counsel must inform the court of the fact of the death within thirty days after it, and must give the name and address of the legal representative or representatives. Naming the representative matters as much as reporting the death, because that is what lets the court move the case forward instead of leaving it suspended.
The consequence the rule states
Failure of counsel to comply with this duty is expressly made a ground for disciplinary action. It is worth noting both what that means and what it does not. The sanction is directed at the lawyer rather than at the heirs, and the rule does not state it as something that automatically undoes what happened in the case afterwards. Whether particular proceedings taken in ignorance of the death are affected is a separate question governed by other principles. The remedy this rule provides is professional accountability.
How the case moves on regardless
A fallback is built in so that a silent counsel cannot stall the case indefinitely. The court orders the legal representative or representatives to appear and be substituted within a period of thirty days from notice. If no legal representative is named by the counsel for the deceased party, or if the one named fails to appear within the specified period, the court may order the opposing party, within a specified time, to procure the appointment of an executor or administrator for the estate, who then appears for the deceased.
Who bears the cost of that
Where the opposing party is put to the trouble of procuring that appointment, the rule provides that the court charges in procuring it, if defrayed by the opposing party, may be recovered as costs. So the burden created by the omission can be shifted back at the end of the case. For heirs, the practical lesson is not to assume the lawyer has attended to this. Confirming that the death has been reported and a representative named is a small step that heads off a much larger problem.