We have movies and shows like Dexter and Batman, V for Vendetta etc. that run down to the noble, tragic vigilante cleaning the streets from the garbage the judicial system refuses to clean. I guess there's something compelling about people operating just within the gray zone of morality but does what happens in show biz transcend to society at large? Our entire judicial system is based on an eye for an eye so it is only natural that a part of this seeps into our individual values as well. Does this make vigilantism right though? Inherently, it implies a distrust of the judicial system and of gouvernment in general that implies violating established rational judicial conventions for irrational emotional outbursts. It is also a strict violation of Kantian principles. Even given "right" and "just" motives, a society where everyone feels they are justified to kill/hurt others would be implicitly irrational and destabilized. Not to mention the fact that violence tends to breed more violence...it's a hard topic to consider because there are a lot of positives as well. Action over apathy. Emotional closure for victims of heinous crimes. An implication that even those privileged/rich/lucky enough to escape the judicial system with terrible sins will not escape the principle that "what goes around comes around." I'm personally torn on this, so I think it makes an excellent topic to debate. Are there degrees to vigilante justice? Is it permissible under certain circumstances but frowned on upon others? Or should it be absolutely forbidden? Just an example that can be used as a typical case study...
To you're general question interesting take that I mostly agree with: I think some amount of vigilantism is inevitable. Because we don't want to live in a police state, our police will be generally poor at protecting people, and fair at best at administering justice. So some people will be frustrated and take justice into their own hands. We should punish it, but we should recognize it for what it is and consider it in potentially reducing sentences and such. "He needed killing" shouldn't be a valid defense, but if someone's actions are in response to injustice done to them (or their neighbors), that should be considered in sentencing. To this specific instance, I don't think I could send a guy to jail for killing a man who raped his two-year-old daughter. If there was ever a justifiable homicide, that's a justifiable homicide.
Batman and V for Vendetta (can't say on Dexter) do not glorify the vigilante though. They are both presented as dark figures and the end result for either can never be happiness. Neither promotes the value of vigilantism, but rather proposes the idea that a society can be so corrupt that one person must take up the "cape and cowl" in order to move others to demand justice.
I think there's an undercurrent of frustration among all of us in how justice is administered. Whether it's a corrupt and crony government or a police force that can't do much right. In accepting or passively condoning vigilantism, we like to romanticize the act as promoting "our cause" or representing the unheard. But sometimes the best way to become heard is shedding light on those who can't bring attention unto themselves. We're in a specific demographic where knowledge, information and possibly money is at our fingertips. There's no justification for us to invoke or accept violence in order to accomplish a lazy and fleeting sense of bloodlust or justice. What if he gets angry and murders again? We could've spared that person's life (and the rapist's...) if the murderer received proper treatment. Heck, I'd feel the same way, but sometimes these thought exercises leaves out unintended consequences.
My reaction isn't logical, it's emotional. I wouldn't support the death penalty for a child rapist, so logically I shouldn't support a reactionary murder of a child rapist. It's still honest. Were I on a jury where a man admitted to killing a man who raped his 2-year-old daughter, I couldn't vote to convict. Were I his judge, I couldn't send him to jail. To be fair, though, I would think that many people who wouldn't murder under any other circumstance could be driven to it by their young child being raped.
Spoiler <a target='_blank' title='ImageShack - Image And Video Hosting' href='http://img100.imageshack.us/i/thecoon.jpg/'><img src='http://img100.imageshack.us/img100/2205/thecoon.jpg' border='0'/></a>