Presidential Power over Supreme Court Decisions

I calculate U.S. presidents’ power and power use concerning the ideological direction of U.S. Supreme Court decisions through their ability to appoint replacements to the Court, over the period 1946 through 2001. I test hypotheses concerning factors affecting appointment power and power use, and examine their effect on Senate confirmation votes. Of nine presidents, four have had the ability to affect the direction of more than 25 percent of Court decisions for sustained periods of time. Strongly ideological power use in appointment is found for four also. Senate confirmation votes have tended to be more favorable when the president has more appointment power.