Duke Gerald, Peter's brother, refuses to tell about where he had been in the night, in order to protect Mrs. Grimethorpe; he risks being hanged for a murder he did not commit rather than betray her.
Duke Gerald refuses to tell about where he had been in the night. This was to protect Mrs. Grimethorpe. Duke Gerald is Peter's brother. He risks being hanged for a murder. He did not commit a murder. He did not betray her a murder.