Here, a self-possessed Isabella is shown in the process of independent judgment. Her anger at Angelo is icy and she does not lose control when her tears come. When she agrees to be directed by the Friar still further, she is motivated not by respect for the Friar but by the desire to punish Angelo, which she cannot accomplish alone. The Duke may be interested to see her reaction to his false information or he may be setting up his test of her capacity for forgiveness in the trial scene. His stage position may be on a level with that of Isabella, or even inferior to it.
Women are ten times frail, after all.
Isabella has a terrible temper to struggle with, and she also has a judgmental streak. When she hears that the Friar's elaborate intrigue has not saved Claudio's life but has cost it, she lashes out at the Friar. This Duke may be anticipating an outburst from Isabella, but even so he may be surprised at its ferocity. He may be condescending toward Isabella, kindly or sternly so. This Isabella may attempt to gain the stronger position and the Duke may give stage in self-defense, but these positions may be reversed by the end of this encounter.