You would be amazed how often, during delibertations, the jury refers to the law/judge's instructions. The pages are dog earred within a day. Agree, agree, agree. We must and we do try to follow the law.
If Westerfield eventually comes clean about why he did what he did to Danielle he just might end up blaming alcohol. Or perhaps a "porno made me do it" like Ted Bundy did.