The Supreme Court has struck a blow against the prosecution of corrupt public officials. The wound isn't fatal, but it needs to be treated promptly by Congress.

The Supreme Court has struck a blow against the prosecution of corrupt public officials. The wound isn't fatal, but it needs to be treated promptly by Congress.

In a series of rulings Thursday with a direct bearing on the trial of former Illinois Gov. Rod Blagojevich, the court restricted a federal fraud statute often used against allegedly crooked pols, as well as other white-collar criminals.

Some of the charges against Blagojevich are based on the statute the Supreme Court has weakened. But the ex-governor shouldn't celebrate prematurely. His prosecutors had anticipated these rulings. Months ago, they obtained a fresh indictment shielding their case against precisely the sort of action the high court has taken. As U.S. District Judge James Zagel told the Blagojevich defense team at trial Thursday, "My preliminary reading is that it may not offer a lot of hope for you."

Still, in the future, it will be more difficult for prosecutors to bring some corruption cases now that the court has limited the so-called "honest services" statute to fraud schemes involving bribery and kickbacks.

Over the past two decades, honest services fraud has applied widely to those who misuse their positions of public trust for private gain — former Illinois Gov. George Ryan among them. It was the very vagueness and malleability of the law that made it so useful to prosecutors — and, the Supreme Court now says — offensive to the Constitution.

All nine justices had one problem or another with the current application of the honest services statute. The majority, including dedicated corruption-buster John Paul Stevens, favored narrowing the scope of the law, while justices Antonin Scalia, Clarence Thomas and Anthony Kennedy voted to dump it altogether.

Thursday's rulings throw up for grabs the convictions of executives Jeffrey Skilling of Enron Corp. and Conrad Black of Hollinger International Inc., former parent of the Chicago Sun-Times. Lower court judges will have their hands full sorting out those convictions in light of Thursday's ruling.

Will Thursday's findings discourage future cases? Maybe not so much: Many white-collar criminals have committed offenses that can be charged under other statutes — conspiracy, racketeering and mail fraud to name three. So prosecutors can proceed by framing their cases around accusations other than honest services fraud.

The biggest impact of Thursday's rulings will be felt on cases that don't involve corporate chicanery documented in voluminous records, or public corruption captured on incriminating wiretaps. The 2006 conviction of Chicago's Robert Sorich, by contrast, stands out as the type of case that might never have been brought if the court's latest restrictions had been in effect — and that would be a shame. The conduct of Mayor Richard M. Daley's patronage chief in rigging the city's hiring and promotion process to favor political insiders goes to the heart of corruption, Chicago style.

Attorneys for the defendants in that case essentially argued that their clients were innocent because they hadn't personally profited from their bad acts. Thursday's rulings have the net effect of pushing prosecutors to allege honest services fraud only in cases where defendants didn't participate in bribes or kickbacks. The problem: Public officials and corporate executives often cheat victims without receiving bribes or kickbacks. In the Sorich case, for example, prosecutors contended that the defendants profited not from bribes or kickbacks but by keeping their jobs and their clout. We agreed with that verdict: A job is a thing of great value.

After Thursday, though, federal prosecutors will have to base some cases on less pliable legal theories than the honest services fraud of yesterday — and develop more specific evidence to convince juries (and judges) that a crime has occurred.

The net effect, then, likely will be fewer anti-corruption prosecutions. Sleaze-plagued Illinois stands as Exhibit A for why that shouldn't be the case.

What to do? Congress needs to refine the honest services fraud statute so it both conforms to the court's rulings and gives law enforcement optimal flexibility to bring criminals to justice. Through a remarkable footnote within one of Thursday's rulings, the court majority invites Congress to act, posing questions that need to be answered for a future honest services law to pass constitutional muster. The Justice Department needs to put forward a proposal as soon as possible, and Congress needs to adopt a legislative fix.

We hope federal lawmakers from Illinois will lead that charge.

Otherwise, the talk among prosecutors targeting corruption will turn to the ones that got away, instead of the ones that got put away.