I don't think one has to order people to break the law. I think it's easier to establish aggressive incentive systems that encourages employees to act very single mindedly. I also think it's easy to undermine internal controls by putting incompetent people in charge who are easily intimidated with bad performance reviews.
That the (whip boy) trader was executing trades as ordered by his (master) superiors in his own name, i.e. taking all the risk, but sharing the profit?