I don’t know. All I know is clearly it’s not a deterrent. The media glorifies these mass shootings and gives the shooter so much fame at the time of the incident but we rarely see the final outcome in the news.
I lived in Arizona at the time Jared Loughner went on his mass shooting spree in Tuscon where he shot Congresswomen, Giffords, District Court Judge, Rolls and eleven other bystanders and although the shooting itself was all over the news for a week I had to search to follow the aftermath of what would become of Loughner until a year later when an article popped up in the Arizona Republic newspaper.
His crime earned a great deal of fame but not his consequences and this seems to be the norm with the media. I don’t know for sure, I have no scientific data, no proof of any kind but I can’t help to feel, in my gut, if the punishment received as much attention as the crime then maybe something would change. Even the smallest change might shift things.
I don’t know.