Your feelings concerning the hypothetical of a family member or someone else you personally care about being murdered are not trivial to the larger picture.
Well, not trivial, but a single person (especially the least lucid person on the subject, the victim) can get as flawed as it gets, while a more objective and detached "system", is bound to be more fruitful.
And this is how it works right now, really (to a degree, anyway).
"Good" citizens should feel protected and supported by society, and that's true, but the scope, the
nature, and the reach of this "protection", is highly debatable.
Afterall we don't cut hands for theft anymore, do we? I think culture can be influenced and shifted towards an even less revenge-based system, and still mantain that degree of "social tranquillity" needed.
Without the death penalty, the chances of revenge murders jump quite a bit. If the family members cannot seek their perceived justice on a person who has murdered one of their own, they may be tempted to enact revenge on the murderer's family. Or perhaps, if a convicted murderer's life sentence is overturned and released, the victim's family will be tempted to kill the person themselves. In a society, which people are more willing to take matters in their own hands, like American society, a federal death penalty ban increases the probability for family wars and vigilantism.
Well, considering that the majority of the countries do not have death penalty, i wouldn't consider that a fact at all.
Thing is, the "perceived justice" is too vague of a term to be applied as law.
For the sake of argument, if you grope my ass and i think that "justice" is for your dick to be cut off, i'm gonna have to deal with the fact that i don't get what i want, and settle for something more appropriate.
As long as the victims don't feel betrayed by society, i don't see "family wars" being a concrete problem (and it's not that common for families to actually go through with personal vendettas), the only vigilantes i've heard of, are entitled douchebags (unrelated to the victims) who feel the need to release some anger and violence, using justice as an excuse.
Again, there
must be a sense of protection, but i never meant to simply treat criminals with the gloves, for the sake of being good at all costs, i'm saying we should follow a logic less based on "throw them in for X time and forgot about them" and more something like: "let's look into this more closely and let's ask ourselves what this people are gonna be, once they're out".
Currently (at least in many countries) Jails, look like places where you go to get even more broken and fucked up, no matter what you did, which is absurd, to me; even though the basic idea IS the one i'm talking about (again, to a degree).
I think some people, when they think about the concept of
rehabilitation, picture a scumbag murderer, social engeneering an hippie psychologist who can't tell his as from his mouth, in a pseudo-summer camp.