A powerful case can be made that the most important and lasting decision a president can make is the selection of a Supreme Court justice.
The Constitution describes the president’s authority in just a few paragraphs. At the core of executive power is the duty to “take care that the laws be faithfully executed,” but a massive federal bureaucracy does much of that work, and there is often very little discretion in how laws shall be enforced. Moreover, Congress decides what laws will be enacted and the courts have the final say in how they will be interpreted. The president makes foreign policy and serves as commander-in-chief, but congressional approval is required to implement policies such as treaties and trade agreements and to finance military ventures. The presidency is a powerful office, of course, but fears of an “empirical presidency” are quite overblown.
When it comes to Supreme Court (and lower federal-court) appointments, however, the president has an extremely important constitutional role. Only the president can select persons who will be judges and, once appointed, they serve for life. While the Senate must confirm judicial appointments, it seldom withholds its consent if the nominee is truly well-qualified.
Supreme Court justices often hold office for decades. Justice Sandra Day O’Connor, who resigned in 2005, served for 24 years. Chief Justice Rehnquist, who died that same year, joined the Court in 1972 and held his position there, first as justice, then chief justice, during seven presidencies. He and his two predecessors as chief justice held office collectively since the first year of the Eisenhower administration. On the current Court, Justice John Paul Stevens, the senior justice, is going strong at age 87, a veteran of 31 years on the Court — nearly eight presidential terms, an appointee of President Ford.
Three additional factors make every Supreme Court appointment extraordinarily significant. First, the Court is nearly evenly divided in a third of its decisions every year. Thus, one or two justices can change the outcome of the most controversial cases. For example, midway through the decisions the Court will render between last October and the end of June, there have been twelve cases where a one-vote shift would have produced a different result. Justice Anthony Kennedy, appointed in 1988 when Judge Robert Bork was rejected by the Senate, was the decisive vote in all twelve.