catalier testified that she favors homicide. would you agree with that? would respectfully disagree with that. >> reporter: the defense conclusion, it wasn't alex who killed emily, it was what was in those pill bottles. >> this is the marital issue. this is what he screamed about, and he howled about. but no one would listen. do justice to alex fazzino. find him not guilty. >> reporter: jurors would now have to decide if alex fazzino was a killer, or a wrongly accused husband who had tried only to save his wife. >> reporter: coming up. >> you prepared for a guilty verdict? >> yeah. >> reporter: two families on edge. four years of questions. the verdict at least. when "dateline" continues. a user without getting ripped off. you could start your search at the all-new carfax.com that might help. show me the carfax. now the car you want and the history you need are easy to find. show me used trucks with one owner. pretty cool. [laughs] ah... ahem... show me the carfax. start your used car search and get free carfax reports at the all-new carfax.com. today's s