Now the defense has introduced data from Tamerlan Tsarnaev's computer to argue that it was this older brother who was the mastermind behind the Boston Bombing. Here is the coverage by Pamela Engel in BusinessInsider.
The hoped-for result will be that jurors will conclude that Dzhokhar Tsarvaev was a mere follower. A kind of rank-and-file solider in the domestic terrorism which caused so much human tragedy. The symbol of that is the late Martin Richard.
Twice, during the guilt/innocence part of the trial, some jurors wept when the details of young Richard's death were presented in court. His sister also lost part of her limb. This double hardship for the Richard family has become sticky globally.
Jurors, being the human beings they are, might not find significant the difference between mastermind and the person who simply carried out orders. That distinction didn't get members of the Nazi party off the hook when it came to prosecuting war criminals. The assumption is that certain kinds of behavior are verboten in a civilized society.
On a micro level, let's apply this to those who harm our animal companions - or any animals. When we go after them, both through law enforcement and in courts of law, we pet parents and animal protectors don't distinguish who's who on the chain of command. We are out for the maximum punishment permitted. And, we figure that the miscreants are damn lucky we didn't take "justice" into our own hands.