The end of a Supreme Court term is often the most interesting. The cases that produced the biggest arguments are delayed until the last minute — and that minute is upon us.

The term ends next week. It is expected that the final rulings will appear on Monday. It is then that the court will decide whether to throw out the Sarbanes-Oxley Act.

If it does, it will use the same basic argument it used Thursday. It will blame Congress for writing bad laws.

And that will clear the way for Congress, if it has the will, to swiftly rescue corporate reform and assure that future crooked corporate and government officials cannot take advantage of the rulings.

In one case decided Thursday, Jeffrey K. Skilling, the former chief executive of the Enron fraud, persuaded the Supreme Court that the concept of committing fraud through depriving an employer of “honest services” was not adequately defined in the law.

If the executive took a bribe or a kickback, then that is illegal under the law, the justices concluded. But if he did something else equally outrageous, the law is too vague and is therefore unconstitutional.

For Mr. Skilling, the victory is only partial and could prove fleeting. The justices refused to order a new trial for him. There were other legal theories advanced by the government in charging Mr. Skilling with conspiracy to commit fraud, and the lower courts will now hear arguments over whether the verdict was amply justified by evidence supporting the other theories.

The high court was equally kind to another disgraced corporate executive. Using the Skilling case as a precedent, it threw into doubt the conviction of Conrad M. Black, the newspaper baron who controlled The Daily and Sunday Telegraph of London and The Chicago Sun-Times. The lower courts will consider whether other prosecution arguments can still justify the verdict.

The decision expected next week is nominally about the Public Company Accounting Oversight Board and concerns an obscure constitutional clause regarding presidential powers. But it could lead to the entire Sarbanes-Oxley Act being thrown out.

The Sarbanes-Oxley Act was passed by Congress in 2002. The Enron scandal — in which it turned out that one of the largest companies in America had ridden roughshod over, under and through accounting rules to report billions in profits when it had no hope of paying its debts — got that effort started. The final push came when the WorldCom scandal broke.

Accounting firms had largely escaped any real regulation before, and the law created the board to inspect and regulate the firms. Board reports have forced major firms to change practices, and the board is generally viewed as having done a good job.

Under the law, the five members of the board are appointed by the Securities and Exchange Commission but are legally not government employees. The board is financed by fees paid by publicly listed companies, and its budget is subject to approval by the S.E.C.

The argument before the court is that under the Constitution, Congress should have allowed the president — or someone he directly appoints and can remove at will — to make the appointments. That argument could well appeal to some justices, particularly Samuel A. Alito Jr., who has supported stronger executive power.

By itself, that dispute over appointment powers might not be too important. But in passing the Sarbanes-Oxley Act, Congress did not put in a severability clause — a normal part of many laws saying that if part of the law is unconstitutional, the rest can stand on its own. So that has raised the prospect that the entire law would fall at the same time.

Out would go requirements for audits of corporate financial controls and for corporate executives to certify that their financial statements were accurate, among other things.

Just what Congress might do if that happened has become a subject of some speculation. Some corporate officials fear that in the current climate, Congress could enact new and tougher regulations. “It is conceivable that the re-proposed legislation would become a Christmas tree on which every ornament of corporate reform and governance will be hung,” said Susan Hackett, the general counsel of a trade group for corporate lawyers, the Association of Corporate Counsel.

But there are also signs that Congress is in no such mood. The financial reform bill that is expected to be passed seems likely to repeal the requirement for audited financial controls for most public companies, leaving it effective only for those with revenue above $75 million.

It also appears likely to grant corporate boards one of their greatest desires, by blocking planned S.E.C. rules aimed at permitting dissident shareholders from putting director candidates on the ballots sent to shareholders by the company. Instead, it would allow no such nominations unless the dissident owned at least 5 percent of the stock, a very high level.

In 2007, some of the same senators now supporting that provision, including Christopher J. Dodd, the Banking Committee chairman, argued that a 5 percent figure would gut any such rule.

It is interesting to consider why the court thinks it is Congress’s fault that it must rule as it did. The legal concepts at stake were largely based on judicial opinions beginning in the 1940s. The court blocked those opinions in 1987, saying that the law did not justify the “honest services” doctrine and inviting Congress to fix that.

Congress did just that in 1988. But now the justices say Congress did not define the doctrine very well. So it looked at the pre-1987 rulings and decided that they amply established that bribery and kickbacks were covered. But there was not enough consensus on other ways of violating that doctrine, like simple thievery. So Mr. Black and Mr. Skilling may walk. If Congress is unhappy, it can pass a better law.

If ever there was a corporate executive who viewed shareholders as inconvenient pests, it was Mr. Black. Eventually, after those shareholders complained over and over, a board committee advised by Richard C. Breeden, a former S.E.C. chairman, concluded that Mr. Black and his colleagues had been running a “corporate kleptocracy.” Facts the committee set out led to the Mr. Black’s conviction.

Mr. Black explained his concept of corporate governance in a 2002 e-mail message when he was under criticism from shareholders for excessive personal spending of corporate money:

“I’m not prepared to re-enact the French Revolutionary renunciation of the rights of nobility. We have to find a balance between an unfair taxation on the company and a reasonable treatment of the founder-builders-managers. We are proprietors, after all, beleaguered though we may be.”

Thanks to the Supreme Court, he may soon feel less beleaguered. Next week, all of corporate America may feel the same way.