He looks briefly uncertain, but if anyone was going to punish him for it, it'd be his warden, so.... "If you're. Sure." He knows there was at least one he killed just because he didn't want to leave a witness. That wasn't self-defense, that was programming.

"What if one was already down," he says after a moment more, looking down at his hand digging into the blanket. "And I killed him, anyway."