IN MID-DECEMBER, when the Department of Defense issued its proposed regulations on military-discharge review boards and the treatment of veterans with "bad paper" (other than honorable) discharges, it was apparent that considerably more work still needed to be done on them. The regulations were marked by a vagueness and lack of uniformity that raised questions about how helpful they would actually be to veterans seeking to have their discharges upgraded. In addition, it wasn't at all certain that the regulations fulfilled what Congress had in mind when it passed the legislation two months earlier. This is why a recent letter from Sen. Alan Cranston (D-Calif.) to Defense Secretary Harold Brown is an important contribution to the discussion. Sen. Cranston, the prime sponsor of the legislation, is in a fair position to have an idea whether the regulations carry out what Congress intended.

Sen. Cranston, to begin with, notes that the regulations omit provisions for making what are called "second determinations," the reviews that would determine the eligibility for benefits of those who went through the Ford and Carter programs and earned an upgrade from "undesirable" to "general" or "honorable." A second omission involves the opportunity to apply for upgrading by "bad paper" veterans who have been denied an earlier upgrading, as well as those whose less-than-honorable discharges go back more than 15 years. On the last point, the law waived the 15-year statute of limitations, which meant that several hundred thousand World War II and Korean War veterans could now apply. But a reading of the proposed regulations reveals that virtually no way exists for those veterans to know that they are eligible.

Sen. Cranston touches on other flaws: the department's weak effort to ensure that the applicants have access to attorneys, the failure to provide for an evaluation of the reasons for the original separation, the absence of a provision requiring the review board to consider whether the reason that led to a "bad paper" discharge was based on the individual's conscience. The latter was a part of the Carter program.

These suggestions of Sen. Cranston are both useful and needed. It is regrettable that they even have to be offered. It is not enough that the discharge-review law as passed last October had a number of serious flaws. Now Sen. Cranston is compelled to come back and call for improvements in the regulations that grew out of that law. Still another branch of government - the courts - may enter the picture if the National Military Review Project of the American Civil Liberties Union challenges the legality of the final standards. The project's officials have already argued persuasively that the regulations, in their current form, suffer critical defects.

All of this, sadly, is part of a pattern. Across the spectrum of health, education and other benefits, large numbers of Vietnam veterans are finding their needs and rights ignored. In this particular area the hardship is especially great, because the "bad paper" veterans constitute the one group most likely to be plagued by high unemployment and severe readjustment problems. The next response must come from the Defense Department. Serious criticisms of the regulations have been made. For Secretary Brown to dismiss these criticisms is likely to prolong hardships that have persisted long enough.