Khalid Sheikh Mohammed Perpetrators Legal Proceedings Suspects Key Figures Accused Individuals Conspiracy Charges Guantanamo Bay Alleged Terrorists Legal Accountability Al-Qaida Victims Co-conspirators Legal Cases Plea Agreements Military Commissions Mass Murder Al-Qaeda Terrorist Trials Accused Plotters Public Perception Zacarias Moussaoui Conspiracy Al Qaeda Victims' Families Accused Terrorists Defendants Military Trials