Stepping back and asking a few questions.
1. Do we have an increase in shootings in schools? ..................... I would say Yes.
I'm 75. I can't remember any school shooting 50 years ago. I went to a all boy College preparatory school in Chicago in 1954. There were 4,500 boys enrolled. We did not have police stationed at the school. All the Chicago schools do now.
2. In Chicago where they have had as many as 900 homicides in one year, who is committing the crime?
Crime in Chicago - Wikipediahttp://en.wikipedia.org/wiki/Crime_in_Chicago
Homicides in Chicago 1990-2012
The answer to the number two question is easy. In Chicago 90 % of the crime is committed in 10% of the geographic area in Chicago.
You can see a nicely colored chart by copying the Wikipedia URL above.
I can go further on the homicides in Chicago.
Of the "Offenders" = 90% have prior felony arrest records
But there is a little surprise with the backgrounds of the Victims > about 70% - 80% of the Victims have prior felony arrest records
The other factor is drugs are involved in about 80% of crime.
The African American murder victimization rate was approximately 34 per 100,000; the Hispanic rate was 11 per 100,000, and the white rate 3 per 100,000.
Over 75% of victims and 88% of offenders had a prior arrest history.
11% of armed robbery victims were female,
50% of domestic victims were female, and
7% of gang-related victims were female.
31% of armed robbery victims were over 45 years old.
29% of domestic-related murders were committed by women.
From 1991 to 2005, 19.2% of armed robbery murder victims were white, and only 4.3% of armed robbery murder offenders were white.
What that says is most crime is black on black and most of that is mostly in localized black communities and mostly committed by 17 - 25 year olds.
That's crime in general.
Our Media / Press usually ignores all that crime.
They love the Zimmerman / Martin, the Duke LaCrosse, the Columbine and the Newtown type.
The race baiters love it
The far left Libs love it
and Our Media / Press love it
Anything they can turn into a serial saga like the OJ Simpson murder.
So we have two kinds of crime.
The run of the mill mostly black youth on black and the crime that invades society with sensation murder that can be exploited.
Are there any common characteristics between the two?
What are the distinct differences - particularly in the mass shootings?
Well in the Mass shootings - in every case
1. The Perp told other people of their intent.
2. The Perp or Perps were mentally unstable
3. The Mental instability was known by more than just the parent.
4. It was known by responsible people - people that could have interceded with just a little more authority.
Stopping Newtown type of crime.
Nancy Lanza had gone to court to institutionalize Adam. (Without success)
There needs to be a way to temporarily have some kind of authority intercede on an emergency basis.
What are the other society changes?
Drugs sex permeate the entertainment media / industry
I'm sleepy I may reply to a reply to add more