SHARE THIS VIDEO —
Analysis: School Shooters have preoccupation with Columbine massacre
School shooters usually have a preoccupation with previous school shootings. NBC's Tom Costello has details.
we and our partners use cookies on this site to improve our service, perform analytics, personalize advertising, measure advertising performance, and remember website preferences. by using the site, you consent to these cookies. for more information on cookies including how to manage your consent visit our cookie policy.