ONE COULD scarcely find a greater mockery of justice than the court record in the widely disputed Weber case now before the Supreme Court.

Brian Weber, a white male employe of Kaiser Aluminum, claims that he is a victim of "reverse discrimination," that there was "never" racial bias at the Gramercy, La., plant where he worked and therefore no justification for the affirmative action plan he is challenging. Kaiser also would have us believe its discrimination record was clean. But the evidence from the government's own files shows this is nonsence.

Moreover, even if past discrimination were not as clear as it is in this case, there is good reason for the high court to approve the voluntary affirmative action plan involved, which requires that half the trainees for higher-paying skilled crafts jobs be blacks and women.

The evidence of past bias is available in this case, evidence gathered in the early 1970s at the Gramercy plant by federal investigators seeking to ensure that, as a federal contractor, Kaiser did not engage in discrimination. Perversely, however, the evidence did not make its way into the lower court record.

Blacks, chiefly from impoverished neighborhoods in surrounding St. John and St. James parishes, made up 39 percent of the available area work force but only 9 percent of Kaiser employes - and those 9 percent were in the lowest-paying jobs. Threatened by white workers, blacks were afraid to bid for better jobs, the investigators found. They recommended, in fact, that Kaiser's contract with the Steelworkers union cite racial intimidation - "violence" and the "threat of violence" - as grounds for dismissal.

Would the company also stop tolerating the use of "nigger" to address black workers? the investigators asked. Over strong union objections, the company assented. In 1973, policy statements barring racial epithets were posted on all plant bulletin boards.

It should have surprised nobody, then, that only one black could be found at the time among Kaiser's 132 supervisors or that, despite a number of nearby black colleges, the 49 professional workers at the plant were all white.

Blacks had often been excluded, the investigators found, because of the white job "pipeline" (white workers bringing in white friends and relatives), and many blacks who did apply were just not "adequately considered." Similarly, they found, whites were being promoted to foremen ahead of blacks with more seniority. Moreover, the company had waived qualification requirements for certain workers - all white - in transferring them to desirable maintenance craft jobs, the investigators reported.

Nor did women fare well. The company, for example, fired and refused to rehire one woman clerk who committed the offense of having a baby, the investigators found. In addition, despite a 24 percent female work force in the area in 1971, not a single female blue-collar worker punched a Kaiser time card. Even as late as 1976, when six women laborers had been hired, Kaiser was resisting government pressure to employ more female industrial workers. This type of employer attitude helps explain why women and the children they support are overrepresented among the poor and the destitute.

Kaiser agreed to take a number of corrective steps, to make sure, for example, that half of those newly hired for unskilled jobs were black and to hire more blue-collar women. The crafts training program

Naturally, the well-paying skilled craft jobs at Gramercy, as elsewhere, were held almost exclusively by whites. Young blacks aspiring to apprenticeship training for such jobs were excluded by the building trades unions. If they weren't trained, they couldn't be hired.

So in 1974, Kaiser and the Steelworkers union agreed to train blacks for these jobs, one for one with whites, at Gramercy and 14 other factories across the nation. Candidates were accepted for this program by plant seniority from within their racial pools, and a 5 percent goal was set for women (at least on paper). Since Kaiser's past hiring had favored whites, some blacks admitted for training would, of course, be less senior than some whites still line. Among those whites was Brian Weber.

The Steelworkers also signed similar agreements with other aluminium and steel producers. Why this sudden interest by labor and management in training blacks and women for skilled jobs? Since 1965, there had been thousands of lawsuits, compliance investigations and discrimination complaints against the companies and the Steelworkers. As a result of agreements between white union officials and management, as Stanford law Prof. William Gould has noted in his book "Black Workers in White Unions," blacks had been locked into the most miserable jobs at blast furnaces and coke ovens. (For steelworkers, even five years of such labor multiplied 10 times the likelihood of lung cancer.) It was the prospect of joint liability for back-pay awards that brought the companies and union to terms.

Despite the extensive history of discrimination at Gramercy, Brian Weber could say at the district court trial that there was "never" racial bias at the factory. What is equally remarkable is that the court simply accepted the word of two Kaiser personnel officials denying any past bias at Gramercy. For example, a Kaiser superintendent, hired in 1968, contended that since the plant's opening in 1958 management had practiced racial equality in hiring. Listen to his testimony from the court transcript:

Q: And prior to [1969 you hired $] . . . what you viewed as the most qualified applicant, black or white?

A: Yeah.

Q: [The training quota] . . . is a remedy applicable to the black race, rather than a remedy applicable to particular workers who are now being favored for previous discrimination, is that right?

A: Yeah. We do not think we have discriminated inside our plant.

The trial lasted one day. Not one black, not even those testifed about, was asked to take the stand. Yet the judge found that "the evidence" established that the Gramercy plant "had a no discrimination hiring policy" since opening "in 1958." Astonishing. The district court's injunction against the training quota was then upheld by a divided appeals court.

The district court relied on a principle that the legal profession knows as "rightful place." This principle calls for employers to compensate workers they have discriminated against, giving them the positions they would have had "but for discrimination." Thus if a black is elevated over whites in seniority to make up for past unlawful bias, the white workers' loss does not constitute illegal discrimination.

One can sympathize with innocent white male workers who suffer as a result, and in fact some observers have proposed that they should be compensated by the not-so-innocent employer. Indeed, in one case known as McAleer, involving an affirmative-action promotion of a woman over a man by AT&T, the court sensibly required the company to compensate the man for his loss.

But the "rightful place" principle, while unquestionably of importance in many individual cases, cannot by itself undo the immense effects of discrimination in American society on employment opportunities.

Hearing about jobs from friends, neighbors and family, for example, is commonplace - but whites have not generally wanted blacks as friends, neighbors or family. On the contrary, blacks - often with government sanction - frequently have been locked into segregated parts of town, where they could not commute to jobs in white areas and where separate and unequal schools often deprived them of job skills althogether. This is to say nothing of how repeated employer rejection has caused withdrawal by racial minorities, a fear of even applying anymore.

This, of course, gives only the briefest suggestion of the intricate network of practices in housing, schools and employment that worked, as if by design - and in many cases certainly by design - to deprive blacks of job opportunities. How can "rightful place," applied to isolated acts of illegal bias, conceivably cope with the effects of this massive system of discrimination? Indeed, "rightful place" is difficult enough to apply because employers, as with Kaiser in the Weber case, want to avoid any admission of past discrimination that would make them vulnerable to back-pay suits.

Clearly, a different principle is needed. Call it "equal impact"

Happily, the courts have shown the way where minorities have not had equal opportunity to meet job requirements.

For example, seemingly color-blind requirements such as a high school diploma or intelligence test scores have a "discriminatory impact" on blacks, excluding them disproportionately from jobs. Such requirements must serve a "business necessity." Suppose the job performance of workers with the "credential" is not significantly better than that of others. Then the "credential" cannot be required. This reduces the impact of separate and unequal educational opportunity.

In other words, instead of the "rightful place" principle, we can use a principle that might be called "equal impact": any requirement excluding racial minorities or women disproportionately from job benefits must be modified or dropped entirely - unless it serves a legitimate business interest of an employer or a union.

Granted, this principle will conflict with white male interests. No doubt some white students strain to finish high school because of the diploma's presumed value in the labor market. Drop the diploma requirement and these whites lose an advantage. But they acquired that advantage to begin with because many blacks have been deprived of an equal chance to earn that diploma.

Hence the loss of such an advantage by young whites would not be unjust and should not be labeled "reverse discrimination." That would imply unfairness. Removing an unjust handicap to blacks is not unfair to whites. The "equal impact" principle also has the immense advantage of not requiring employers to admit past discrimination, so they are more likely to cooperate.

In the Weber case, it is precisely the lack of equal opportunity to earn seniority that is at issue. Even if this had not resulted from deliberate discrimination by Kaiser, the entire system of American discrimination that kept blacks at the margins of employment denied them the chance to earn seniority.

The Kaiser-Steelworkers' crafts-training quota satisfies the "equal impact" principle. It was designed to reduce the effect of such discrimination.

Weber cried "reverse discrimination" because blacks and whites were admitted, one for one, by seniority from within their racial pools. But a race-blind seniority would only have perpetuated the inequality resulting from a history of discrimination. Moreover, race-neutral seniority serves no "business necessity." In this case, as in many others, seniority does not signifiy any more ability to perform the skilled job.

The 1974 Kaiser-Steelworker agreement, which gave "equal impact" its due, was struck down in 1976 by the courts. For two years, justice was inscribed on a workplace in Gramercy, La. That justice should be returned by the Supreme Court and be writ large for our whole society. CAPTION: Picture, Brian Weber.