User blog comment:Abelskie/The Grimm-ness of Nick/@comment-2255188-20120216040632/@comment-1966944-20120216080244

Nick is basically torn between two worlds. First, he is a Police officer, sworn to uphold the law and protect and serve the community. Second, he is a Grimm, who (according to Aunt Marie and to a lesser extent, Monroe) supposed to track down and kill a variety of creatures in cold blood, before they can do harm, but to do that would violate his oath as a Police officer. Its not a matter of him gaining or loosing his abilities (and I have made that same observation) but a matter of principle. Also, in the psychology of storytelling, you can have your main character be a hero or an anti-hero. Nick, right now, is the hero. Only killing in self-defense and trying to bring justice to an unjust society, whether human or creature. So thus, he is sympathetic to the audience. Once he crosses that line and becomes a "true" Grimm, (providing we believe Aunt Marie's definition of what a Grimm should be) going out and killing any and all creatures, no matter whether they have committed atrocities against humans or to each other, then Nick crosses into the anti-hero arena and becomes a less sympathetic character..