WE ARE WITNESSING an ironic turn in the historic struggle between the executive branch and Congress: a court decision which seemingly promises much greater power for the executive but which, if upheld, would likely lead to the opposite effect.

The Jan. 29 ruling, by a three-judge panel of the U.S. Court of Appeals here, gave a rude jolt to the "legislative veto," a device Congress has relied on for at least a half century to control executive actions.

Specifically, the panel struck down a one-house veto used to disapprove a gas pricing regulation by the Federal Energy Regulatory Commission (FERC). But its language was so broad as to question the constitutionality of legislative vetoes in hundreds of other laws governing arms sales, immigration, war powers, impoundment, endless agency regulations and much else.

The D.C. panel recognized that its finding -- that all legislative acts constitutionally require "presentation to the president and passage by both houses of Congress" -- "may have far-reaching effects on the operation of the national government." But it may have misunderstood those effects.

Many assume the ruling portends a gain for the executive branch, a victory for orderly government, a blow to congressional interference. Think again. If the Supreme Court upholds the overly broad opinion, the net result will more likely be less power for executive officials, a more convoluted legislative process, and continued congressional involvement in administrative decisions.

Bizarre consequences? Not if you understand why the legislative veto was originally adopted. Presidents accepted (indeed, often invited) legislative vetoes because they provided a way to get more power. The bargain was clearly understood by both branches. The president essentially told Congress: "Give me more authority than you normally would, and I'll give you a chance to veto my initiatives." If presidents disliked the legislative veto, Congress would withhold authority.

Courts are familiar with this quid pro quo. In 1977 the Fourth Circuit dismissed a suit by a federal employee who protested that the Senate acted unconstitutionally when it disapproved a pay raise recommended by the president. But the legislative history convinced the court that Congress delegated the salary authority only on the condition that it could, by a one-House veto, disapprove presidential recommendations. The authority and the condition were inseparable.

The FERC case was different. Here the court decided that the grant of rulemaking authority was not tied explicitly to the one-House veto. But that is the exception, not the rule.

The record shows, for example, that the president could not tell Congress: "Thanks very much for the authority to reorganize the executive branch, but I have no intention of recognizing your right to veto my plans." Executive reorganization power and the legislative veto could not be severed.

Other examples abound. Under the Impoundment Control Act of 1974, the president may defer spending unless one house of Congress disapproves. The president is not at liberty to take the authority and ignore the condition. If the legislative veto is unconstitutional, the president will forfeit the statutory authority to defer spending.

He might claim other authorities (statutory or implied powers under the Constitution), but this would merely trigger the kind of fractious litigation we had in the early 1970s under President Nixon.

The Federal Trade Commission Act of 1980 raises a similar issue. Congress, angered by some FTC regulations, enacted legislation requiring future rules to run the gauntlet of the legislative veto. If the D.C. panel's opinion is upheld, the FTC may lose its authority under the statute to issue regulations.

Uncertainties in this area, as in others, would probably force more issues into the courts, with the preponderance of evidence often on the side of the Congress. In the laws covering arms sales, foreign trade, the sale of nuclear fuel, federal salaries, immigration, impoundment and presidential papers, for some notable examples, the delegated power and the legislative veto seem inseparable.

Congress, of course, could rewrite many of its broad delegations of power, and the executive branch also could well lose some procedural benefits. Where there is a legislative veto, presidential proposals are put on a fast-track system. Other privileges include special procedures to discharge committees of an administration proposal, limits on debate, and prohibitions on floor amendments. Without the legislative veto, Congress would eliminate these advantages or require the president to gain approval of both Houses in a bill or joint resolution. Either approach would undercut the president.

The legislative veto is criticized as a backdoor way of accomplishing what should be done directly through the regular legislative process. But if Congress is denied the legislative veto, no one should underestimate its ingenuity in inventing other devices that will be more cumbersome for the president and just as satisfactory to Congress.

President Eisenhower discovered this unpleasant fact in the 1950s when he objected to "committee vetoes" compelling agencies to obtain advance clearance from congressional panels. Attorney General Brownell called this an unconstitutional infringement on executive responsibility.

Undaunted, Congress created another procedure that yielded the same control. A bill was drafted to prohibit appropriations for certain real estate transactions unless the Public Works committees first approved the contracts. Eisenhower signed the bill after Brownell concluded that this procedure -- based on the authorization- appropriation process -- was within Congress' power. The form had changed; the committee veto remained.

If the one-House veto over impoundment deferrals is invalid, Congress will have no trouble devising more burdensome procedures for the president. A harbinger of what might be in the works appears in the Transportation Appropriation Act for fiscal 1982, passed last December. Whenever the president proposes to defer appropriations for various rail programs, the funds must be released unless Congress within 45 days completes action on a bill approving all or part of the proposed deferral.

There is no constitutional problem here, since Congress will act through the regular legislative process. Yet in this case, in effect, the president not only ends up with a one- House veto but a more onerous version. Under the Impoundment Control Act, one House must take the initiative to disapprove a deferral. Under the transportation statute one House can succeed through inaction.

There are other anomalies. Opponents of the legislative veto warn about the workload imposed on Congress by having to review administrative actions. But the workload is likely to be far heavier if Congress has to act positively through the regular process. The temptation will be strong for Congress to grant powers for shorter periods, forcing the president to return to Congress for extensions. Of course either House, by inaction, could deny him the authority.

Other mechanisms are also available to protect congressional prerogatives. Under the Trade Act of 1958, the president could implement certain actions for import relief only by obtaining from Congress a concurrent resolution passed by a two-thirds majority in both Houses. Courts would likely find this type of concurrent resolution constitutional, since it contains a built-in override of a presidential veto. This would come as little consolation to a president forced to locate an extraordinary majority in each House before acting.

The D.C. court, in its FERC ruling, warned that the legislative veto enables Congress "to expand its role from one of oversight, with an eye to legislative revision, to one of shared administration." This increase in congressional power, according to the court, violates the separation-of-powers doctrine.

But with or without the legislative veto, Congress will remain knee-deep in administrative decisions, and it is inconceivable that any court or any president can prevent this. Call it supervision, intervention, interference or plain meddling, Congress will find a way.

If an agency adopts a regulation that offends Congress, legislators can attach language to an appropriation bill preventing the use of funds to implement the regulation. There is no constitutional question about Congress' right to do this, although riders to appropriations bills are far from ideal ways to make law. They are added without the hearings, careful consideration and substantive knowledge that more likely accompany a legislative veto.

Congress also exercises an extraordinary array of nonstatutory controls. The clearest examples are the understandings between Congress and the agencies for "reprogramming": the shifting of funds from one program to another within the same appropriation account. Major reprogrammings must be approved by the committees (or subcommittees) with jurisdiction over the program.

This is simply one more quid pro quo between the branches. In return for the flexibility of lump-sum appropriations, agencies agree to abide by reprogramming guidelines and committee clearance. No one wants to return to line-item funding. Since this type of control is informal and nonstatutory, it is difficult to conceive of a legal issue that might reach the courts. But the involvement of Congress in "shared administration" is just as real and binding.

Judicial warnings about shared administration seem unrealistic in view of the extensive overlay of statutory and nonstatutory controls. Certainly it is extravagant and hyperbolic for the D.C. Circuit to suggest that legislative vetoes put us on the road to congressional tyranny. If the courts are serious about "untangling" the rights and powers of the three branches, they have their work cut out.

Shall they prohibit the president from making substantive legislation through executive orders and proclamations? Will courts resurrect the 1935 rule requiring Congress to delegate legislative power with clear standards? This would be a revolution in itself. Should we consider placing all independent commissions under the executive departments, thereby tidying up the system of three branches? This has been tried more than once, without success, and for good reason. Can we no longer tolerate adjudication and "quasi-legislation" by the agencies? Should we eliminate "legislative courts" (established under Congress' Article I powers)? For that matter, is it time to ask the courts to pull back from their own involvement in legislation and administration?

It is too glib for courts to tell Congress that if it disagrees with what the president and the agencies are doing, it should act through the regular legislative process. The regular process is subject to a president's veto, creating the need for a two-thirds majority in each House to override the president. Without the legislative veto, Congress is placed in the dilemma of delegating authority by a majority vote and then needing a two-thirds majority to recapture control. That is why both branches agreed on the legislative veto for reorganization authority.

The legislative veto in the War Powers Resolution of 1973 was meant to extricate Congress from the situation it found itself in under Preident Nixon: able to attract a majority vote in each House to deny funding for the Vietnam war, but unable to secure a two-thirds vote when Nixon vetoed these restrictions. Critics of the legislative veto have not addressed this problem.

Nor is it enough to advise Congress that legislative vetoes would be unnecessary if it would only delegate with precise standards and clear policy.

Congress has no doubt used the legislative veto to sidestep difficult questions of national policy; it can be a convenient and irresponsible substitute for making legislative decisions. But the veto allows Congress to review specific proposals under circumstances that no one could foresee when the authority was first delegated.

For many issues facing government today, the legislative veto is practical, appropriate, and constitutional. Striking it down is not a step to be taken lightly.