Throughout your campaign you've witnessed his atrocities first-hand, horrifying images of mutilated and rotting corpses. Innocent people young and old--men, women, and children--butchered mercilessly and dumped unceremoniously in mass graves. The images of these crimes haunt your dreams every night and will likely stay with you for the rest of your life. As your face the man who butchered your people without remorse who continues to display no guilt of conscious the men under your command, justly furious at the callous disregard for the lives of their people this vile man has shown, quietly state that if he were to have an "accident" that no one would say anything. You've served with these men for years; you have no idea they're being completely honest. You, yourself, can't help but feel rage at the war crimes you've witnessed. Technically you're expected to arrest the general so he can be sent to the Hague, but no one would miss him if he were to suddenly die "unexpectedly". There are no other witnesses. Your committed and decorated service record has earned you many allies in positions of power, none of which are willing to question your "official" account of the encounter.
What you face is not a question of legality but of morality. No matter your choice, the outcome remains the same: the mass-murderer is brought to justice. You will face no punishment either way. Your men respect you enough to follow your decision no matter what. You'll be remembered as a hero regardless of your choice.
Will you kill the butcher or spare him?