In the level in Jeruselum when Lambert tells you to kill Dahlia Tal it is up to you wether you kill her or not. If you do there are three guard in the courtyard when you are escaping but if you don't then there aren't great!!...right. No, because if you don't then Dahlia and three of her friends are in the windows sniping at you so as I say. It's up to you.
Knocking out two guards
To knock out two guards at the same time simply fire a diversion camera out of the sc-20k at the wall or the ground and then press X to make a whistling sound and when the guards come over press Y and gas will come out and choke them both.