Of course, any deterrent effect is reduced the more you reduce the horror of it. Back in the old days of hangins, guillotine beheadins, breakin guys on the wheel, and such, executions were public, and generally drew big crowds. People would bring they little chillinz to watch. Part of it was just the spectacle and festival of it all, I spect, but there was another, educational, aspect to it.
Very few 5 and 6 year old kids who see a guy's head fallin into a basket and then watch his neck just keep gushin out blood fail to be strongly impressed. Sumthin they remember years later, even at times when they seriously wanna off some guy, ya know? Talkin for my own damn self, they's probably 3-4 homeys I woulda stuck a pitchfork in by the time I was age 12, except for I didn't wanna git strung up like them guys I had seen down at the town square.
Even back in the 30's and 40's before movies they would show newsreels (either before or after the cartoon, I forget now), showin some sorry soul bein fried in the electric chair, the top of his head smokin, his face expandin like a balloon, and alla that. Kids loved it, but it terrified them, too, of course.
Not now, though. No one is allowed to broadcast executions, not even if it's just stickin a needle in some guy's arm and watchin him quietly lay there, instead of dancin on the end of a rope for a good long spell. Young-uns can't be deterred by sumthin they can't even see, generally speakin. So, ya see, that why the murder rate just keeps climbin, they way I figure it.