Free speech doesn't kill people, people kill people. If we want to live in a free society, we must restrict only those acts which initiate violence against others. It's easy to seek scapegoats in the aftermath of trauma. It's easy for politicians to exploit tragedy for their own political ends. But irrational anger is no substitute for a healthy process of grieving.
Somber reflection is better than blindly acting out in anger.
Grief and anger must be channeled appropriately, or we will very likely end up with a society even less civil and wholesome than the one we now live in.