NO DOUBT Ernest Lefever can still be confirmed on the floor of the Senate as the State Department's human rights officer if the White House puts a bit of muscle into it. But the real question, which ought to be considered on allsides while the foreign Relations Committee pauses to ponder the nomination, is why the administration would want Mr. Lefever in the job at all.

That a conservative administration should wish to devise its own human rights policy and appoint someone appropriate to run it is as it should be. Unquestionably there are different ways to go about working in this difficult and sensitive area, and the policy of the last administration was something less than an unalloyed success. The Reagan choice for human rights chief should not be judged in terms of his or her fitness for appointment by Jimmy Carter.

But Ernest Lefever?

Mr. Regan's anti-communism, or anti-Sovietism, keep in mind, is not in doubt. He does not need in the human rights post someone who reinforces that element of his policy. What he needs, we think, is someone who conveys unequivocally that a hard anti-Soviet policy pointed at the large issue of freedom is not inconsistent with a human rights policy designed to enlarge the sphere of individual rights and liberties -- everywhere. Mr. Lefever, through an extended debate and through the hearings on his nomination, has failed utterly to convey this idea. Rather, he has conveyed that he does not understand this requirement at all. Far from adding something of value to Reagan foreign policy, he denies the president the one valid contribution he could be expected to make.

Unlike most others, the post to which Mr. Lefever has been nominated demands of its occupant a clearly visible personal commitment. Mr. Lefever has shown a commitment, but it is less to a grand concept of human rights than to an arid cartoon version of a certain political idea. He believes, he says, that a distinction must be made between friends of the United States with authoritarian and therefore correctable regimes whose excesses should be treated by "quiet diplomacy," and adversaries with totalitarian and therefore incorrigile regimes whose flaws must be assaulted head on.

Perhaps in skilled and sophisticated hands this idea could be refined and made a partial guide to policy. In Mr. Lefever's hands, however, it becomes a bludgeon. He seems to think that a single simple label, authoritarian or totalitarian, can be applied to each country, and that the act of labeling resolves all policy dilemmas. He ignores that, depending on circumstances, it may be helpul both to endangered individuals and to the large cause of freedom to make a public complaint to a country like Argentina. Similarly, it may be no less helpful to, say, individuals struggling to emigrate for Washington to take a quiet approach to a country like the Soviet Union. Mr. Lefever's rigidity and narrowness are a parody of what a productive conservative human rights approach could be.

There is the further matter of the allegations about the way in which Mr. Lefever conducted the institute he previously ran, and the manner in which he has responded to inquires into it. If he has difficulty making a strong case for his personal integrity and judgment in his private business, what reason is there to believe he will do better in handling the public business? The very hint of shabbiness, in someone who professes to be a student of ethics and whose ethical precepts would bear directly on his new duties, is practically disqualifying in itself.