Given the little dust-up over the Senator McCain's comment that he would remove Christopher Cox as Chair of the Securities and Exchange Commission, and questions as to whether the President has such authority, I thought it would be interesting to quote portions of the D.C. Circuit's majority opinion in Free Enterprise Fund v. PCAOB on the subject:

Members of the Commission, in turn, are appointed by the President with the advice and consent of the Senate and subject to removal by the President for cause; its chairman is selected by and serves at the pleasure of the President. (p. 3)

independent agencies such as the Commission by definition enjoy a degree of autonomy in conducting their affairs, including staffing and operations. Yet this independence is not without limits. In addition to the ability to appoint Commissioners, 15 U.S.C. § 78d(a), and remove them for cause, . . . which removal power the Supreme Court has interpreted broadly,[FN8] the President possesses significant additional levers of influence. Most obviously, by appointment of the Commission chairman, who serves at the pleasure of the President and often “dominate[s] commission policymaking,” the President can influence Commission policy and control who directs “the administrative side of commission business, select[s] most staff, set[s] budgetary policy, and as a consequence command[s] staff loyalties.” (pp.23-24)

FN8 The Supreme Court has held that the restrictions on the President’s removal of Commissioners for “inefficiency, neglect of duty, or malfeasance in office” are “very broad and . . . could sustain removal . . . for any number of actual or perceived transgressions.” (p. 24)