In building its case for Senate confirmation of Robert Bork to be a Supreme Court justice, the administration is propagating three myths:

1) Ronald Reagan won the presidency by a "landslide" and is therefore entitled to have a Supreme Court that shares his conservative views. In fact, almost half the electorate rejected Mr. Reagan in 1984 (he got about 54 percent of the popular vote), and a majority rejected his politics in the 1986 congressional elections. Moreover, public opinion polls have consistently shown that Americans disagree with Mr. Reagan on the so-called social issues that come before the court, such as abortion and school prayer.

2) In considering a Supreme Court nomination, ideology is irrelevant; rather, the Senate should examine only the nominee's judicial qualifications. This myth demeans the Senate's constitutional role of advising on as well as consenting to judicial nominations, and it would empower a president to impose his views on the country for years after he left office. Recall the outcry when Franklin Roosevelt sought to "pack" the court in 1937; Mr. Reagan is pursuing the same goal without enlarging the court. It is the Senate's duty to bring ideological balance to the appointment process.

3) A president is entitled to have his nominees confirmed, given reasonable qualifications. This is an appropriate principle for executive branch nominations, since these nominees will serve the president and generally leave office with him. But it has no applicability to nominations to the judiciary, which is a co-equal branch of government whose members serve for life. The Constitution gives the executive and legislative branches co-equal roles in appointments to the bench. ROGER S. KUHN Bethesda

Michael Barone {op-ed, July 9} declares that Robert Bork is "the closest thing we have to a principled believer in judicial restraint" and asserts that his "attackers do not really contest this proposition." Since Judge Bork will restrain himself when reviewing "liberal" as well as conservative enactments and actions, Mr. Barone concludes, liberals should welcome the judge's nomination to the Supreme Court.

It appears that Mr. Barone is unaware of Judge Bork's actual record as a court of appeals judge, as well as of the kinds of cases he has resolved. The vast majority of agency decisions Judge Bork has reviewed during the Reagan years, not surprisingly, have been favorable to business interests and antagonistic to labor, consumer and environmental organizations. The judge has rigidly applied his rules of restraint -- deference to the executive branch and strict interpretation of constitutional and statutory language -- in upholding those decisions. However, in the much smaller class of cases in which businesses have challenged governmental decisions, Judge Bork has often abandoned his own rules of restraint and overturned the agencies involved.

In one recent lawsuit, for example, in which Judge Bork authored an opinion reversing an agency decision adverse to an electric utility, Judge Abner Mikva accused him of "blatant interference with the ratemaking procedures" adopted by the Federal Energy Regulatory Commission. In another case, Judge Bork rejected a National Labor Relations Board determination against a company, prompting Judge George MacKinnon, a conservative Nixon appointee, to castigate him for "trench{ing} on important policymaking prerogatives" of the NLRB.

While Mr. Barone and others in the media have uncritically accepted the administration's packaging of Judge Bork as a neutral, across-the-board practitioner of judicial restraint, his opinions, as well as his own colleagues on the court of appeals, suggest otherwise. They also suggest that Judge Bork, as a Supreme Court justice, would not be as hospitable to "liberal" statutes and regulatory decisions as he has been to the antiregulatory practices he has mainly been called on to review during the past six years.

ERIC R. GLITZENSTEIN Washington

Lincoln Caplan {"If Robert Bork Didn't Exist, Reagan Would Have to Invent Him," Outlook, July 5} accuses Judge Bork of "campaigning" for the Supreme Court by "building his conservative credentials for a generation." Among such credentials, as listed by Mr. Caplan, is Judge Bork's criticism of Justice Powell's majority opinion in the Bakke case. Does Mr. Caplan recall that Justices Brennan, Marshall, Blackmun and White all dissented from the majority ruling in Bakke? (In fact, no justice concurred in full with Justice Powell's opinion.) Surely Mr. Caplan does not mean to imply that Justices Brennan and Marshall dissented from Justice Powell's opinion in order to build their conservative credentials.

DON BOUDREAUX Fairfax

Colman McCarthy's column "What Robert Bork Says" {Style, July 12} is not a helpful contribution to the current debate on Judge Bork's nomination. "The Antitrust Paradox," which forms the basis for Mr. McCarthy's criticism, was published by Judge Bork in 1978, and it has since been an influential part of responsible discussion of antitrust policy. The book is basically a plea for antitrust enforcement designed to maximize consumer welfare and informed by a knowledge of economics. This view of antitrust has been labeled the "Chicago school." While one may disagree with this approach on various grounds, the fact is that it is largely in ascendancy at this time in both the government and the courts. Whatever may be said of Judge Bork's views in other areas of the law, it is simply wrong to say that his views on antitrust are "so far in the fringes of irrelevant extremism" as to disqualify him for a seat on the Supreme Court. JOHN H. SCHAFER Washington