On June 17 President Reagan announced his intent to nominate Justice William Rehnquist as the 17th chief justice of the United States and Judge Antonin Scalia to take his place as associate justice. By all traditional measurements, both are superbly qualified.

No one has contended otherwise. There appears to be unanimous agreement that both nominees have the qualities of intellect, integrity and temperament necessary for service on the Supreme Court.

Nevertheless, several commentators have urged the Senate to scrutinize these nominees carefully because of the possible effect their substantive views might have on constitutional issues the court will consider during their tenure. See, for example, the Post articles by Richard Cohen "Judges Beyond Judgment," op-ed, June 20 and Suzanna Sherry "It's Not the President's Court," op-ed, June 26 . The plain implication is that the Senate should reject them on this ground. We are told that if it is proper for the president to consider ideology in exercising his constitutional power of appointment, it is just as proper for the Senate to do the same in deciding whether to confirm.

I believe this argument misses the mark.

Both the president and the Senate have a responsibility to consider the competence, integrity and temperament of a nominee. By contrast, the right to prefer one philosophical point of view must rest either with the president or the Senate, but not both. The only time the issue really matters is when the president has one philosophical preference and the Senate another. Because their choices differ, one or the other must yield. Otherwise, the potential for perpetual impasse would be built into our appointment/confirmation scheme.

Both the constitutional language and common sense convince me that the right to choose based on substantive views must rest with the president rather than the Senate. The Constitution expressly places the appointment power in the president. The power to appoint includes the power to choose, to differentiate, to decide whether one candidate is preferable to another. Confirmation, by contrast, does not include the right to decide which of all possible candidates is preferable to the others, but only to pass on the qualifications of the person nominated.

In addition, leaving the appointment power where the Constitution puts it makes the whole process more responsible because accountability for appointments is located in one individual, rather than being spread over 100. The president, unlike the members of the Senate, is elected by a nationwide constituency. The only real opportunity the voters have to affect the federal judiciary is through their choice of a president. He alone appoints judges. By contrast, when we vote for a senator, we select one person out of 100 who will vote to confirm or reject the president's appointments.

Refusal to confirm for philosophical reasons must therefore be reserved for extreme cases -- where the nominee holds positions outside the wide range of reasonable constitutional views. It cannot be exercised because the Senate, if it had the power to do so, would have appointed someone else. But the extreme-case exception is inapplicable here, because there is no suggestion, nor could there be, that either Justice Rehnquist or Judge Scalia presents such a case.

I have to ask this question of those who disagree with me: assume that we could turn back the clock to the late 1930s when President Roosevelt nominated Justices Hugo Black and William Douglas or the 1950s when President Eisenhower nominated Chief Justice Earl Warren. Assume further that you were there and were prescient enough to know the enormous impact those appointments would have on constitutional precedents. Would you have urged the senators of those days who would have disagreed with those results to vote against confirmation for that reason?

The whole issue really comes down to a simple unhappiness that these appointments are being made by Ronald Reagan. There is an accompanying refusal to accept either the constitutional provision vesting the appointment power in the president or the results of the 1984 election.

When the voters select a president, they do more than choose the person who can veto Congress' bills, give State of the Union messages and command Air Force One. The selection of Supreme Court appointees is among the most important decisions a president will make. I understand the disappointment of those who wish that Walter Mondale were making these appointments. But that question, whether sorrow over Supreme Court nominations was to be endured by them or by me, was settled on Nov. 6, 1984.

The writer was solicitor general from 1981 to 1985.