When Howard Baker took over for Donald Regan as Chief of Staff in 1987, bringing with him A.B. Culvahouse as Counsel to the President, First Lady Nancy Reagan specifically asked Culvahouse to keep Cox on the White House staff. According to Culvahouse, she and the East Wing staff "liked Chris a lot ... He is a very good lawyer," and his willingness to give up his partnership in a prestigious law firm to join the White House staff only a year before had made an impression. As Senior Associate Counsel under Culvahouse, Cox became deeply involved in market issues and securities issues including then-pending congressional proposals for legislation on insider trading, greenmail, junk bonds, golden parachutes and golden handcuffs, tender offers, and takeovers.