Jean is responsible for the school shooting.

Jean obviously meant well when allowing the students to govern themselves but while that sounds good in theory, in practice it's futile. The students were in desperate need of experienced leaders who could reason with the people. However, being allowed to do their own thing they escalated a bad situation and made it worse. All of the students needed to be kept inside where they would be safer. Instead, they are allowed to stand outside and egg the militia and cops on. When the shooting started everybody ran, some into the gunfire. Jean came running out only to be shot a couple of times as well. Unfortunately she survived. Here's a tip, don't provoke those with firearms and the legal right to use them.