That doesn't make much sense.
Are you talking about tabbed documents in Photoshop? if so, turn them off in Preferences (like most pros).
And when you activate or open a document in tabbed mode, it does come to the front.
I actually entered this question for a user. When he selected a tabbed document it jumped to the back instead of the front. It seemed like a bug, but unfortunately I don't have more info (or his contact info) for more detail.