I think the problem with that solution is because of who would be trusted to do the branding. Would you like the N in your life to be the one who made the decision? If he/she was, how do you think he would brand you?
There's also the problem of the possibility of change. A brand is so very permanent, and I think most people hold out a hope, however unreasonable, that people can change. Not that they will--but that they can.
I think that the key variable in the story of Cain was who did the branding and why. No one now on earth has the same authority and power (nor omniscience, nor righteousness). I would be reluctant to have anyone less worthy wield the brand.
CB
physciatry could do the "branding", after all they are the ones who are doing the labeling ie) sociopath, physcopath, Narsasist....Pedifles etc.... it would be an institution of authority, perhaps physciatry could work with the criminal system, courts, jails etc.... to come up with a system which alerts potentiual victoms to whom they are dealing with, something arround their wrists that can not come off.... anything that is visible to the rest of the populas.......
While it is true that it was God who put the mark on Cain, you have to realise that there was no other justice system in place yet, because there was only Adam-Eve- offspring, Cain and Abel......
If physciatry has the authority to label /diagnose/ then they could have these criminals marked for us, so that our daughters are not dupped by them, because after all they are "cons" they present a different face than whom they truly are