As much as the archduke seems to many people that he is too harsh on Ebony, I take it the other way instead. He is making Ebony question the laws and diplomacies of the country that condemned her for an alleged homicide she did not commit. "Why is this the way it is? Is it because I am a woman? Why are women so disregarded in this society?" It's a way to get people to start questioning everything around us and find our own conclusions. I use it all the time when I come up with concepts for projects, where I have to fine reasons to justify a certain fact for said concept. Questioning her harshly, I feel, makes her break out of her slump, because, had the archduke worded it softly in a roundabout way in consideration of her, she would have definitely started to blame herself again for everything, thus making her feel even more worthless. Wording it clearly here helped her to begin a thought process.
Just an opinion. Although she did have a considerable amount of trauma, so maybe raising his voice at her wasn't such a great idea.
edited some spelling errors