When Dallas police used a bomb-carrying robot to kill a sniper, they also kicked off an ethical debate about technology’s use as a crime-fighting weapon. In what appears to be an unprecedented tactic, police rigged a bomb-disposal robot to kill an armed suspect in the fatal shootings of five officers in Dallas. While there doesn’t appear to be any hard data on the subject, security experts and law enforcement officials said they couldn’t recall another time when police have deployed a robot with lethal intent. […] “If lethally equipped robots can be used in this situation, when else can they...