Whether a deacon or another who is not a priest can grant an indulgence?

❌ Objection 1 : It would seem that a deacon, or one that is not a priest cannot grant an indulgence. Because remission of sins is an effect of the keys. Now none but a priest has the keys. Therefore a priest alone can grant indulgences.

❌ Objection 2 : Further, a fuller remission of punishment is granted by indulgences than by the tribunal of Penance. But a priest alone has power in the latter, and, therefore, he alone has power in the former.