Nehemiah has publicly appealed to the consciences of the rich oppressors standing yonder, reminding them of the law of the Lord and of their moral obligations to their own community. Given the logic of his argument (and no doubt the presence of many oppressed victims), there was nothing left for the nobles and officials to say.
8 and said to them, “We, as far as we are able, have bought back our Jewish brothers who have been sold to the nations, but you even sell your brothers that they may be sold to us!” They were silent and could not find a word to say.