Persons Evil News Today

Some of the most important clues in the boston bombing investigation may lie inside the brains of the suspects, possible abnormalities that experts say could have predisposed them to this kind of horrific attack. here is our chief medical correspondent dr. sanjay gupta. >> reporter: in the wake of tragedy come the inevitable questions, what makes a killer? is there a switch that turns on a rampage? and why? why would someone do this. >> you can say the persons evil. i think thats 13th century th...

>> you can just say the persons evil. i think thats 13th century thinking. i think weve moved beyond that. >> hes the criminologist, and author of a new book anatomy of violence. he said there are biological explanations for violence. he is convinced that brain dysfunction may in part explain the terror unleashed in boston. >> were they just completely normal people who decided one day, you know what, we want to create mayhem. i dont think so. i think its more complicated than that. >> reporter:...

Welcome back. im jake tapper. more on our national lead. they are accused of unspeakable violence ending innocent lives in a senseless act of terror. what could have made two young men with family, friends, and limitless opportunities in this great country turn so drastically against this country? dr. sanjay gupta takes us into the minds of two alleged killers to try to find out. >> in the wake of tragedy come the inevitable questions. what makes a killer? is there a switch that turns on a rampa...