The Supreme Court’s review of a public corruption statute could open an escape route for individuals caught in the influence-peddling investigation centered on ex-lobbyist Jack Abramoff, according to criminal law experts.

The Supreme Court heard arguments Tuesday in two unrelated cases challenging a federal statute that makes it a crime to “deprive another of the intangible right of honest services,— a regulation favored by federal prosecutors in public corruption and corporate fraud cases.

Prosecutors have relied heavily on the statute, particularly in the Abramoff investigation, in part because it provides more legal flexibility than the rigid requirements of charges such as bribery.

But Supreme Court justices expressed concerns Tuesday over whether the law was too vague — which Justice Anthony Kennedy called “the lurking problem here.—

In addition, Justice Stephen Breyer suggested the court could ask the government to address the law’s constitutionality in a future brief for a third case expected to be heard next year.

Any skepticism by the justices could ultimately bode well for individuals charged under that law, including some of the 20 involved in the Abramoff investigation, many of whom accepted plea agreements admitting to conspiracy to committee honest services fraud.

If the court were to overturn the law — which was enacted in response to a 1987 Supreme Court ruling that limited fraud statutes to money and property rights, and excluded the “intangible right of the citizenry to good government— — it could open the door to appeals and allow individuals not yet sentenced to back out of plea agreements.

In some cases, individuals could even see their convictions vacated.

“That is conceivable even for people who are already serving their sentences,— said Stan Brand, a white-collar defense attorney and former House counsel.

Brand noted the example of ex-Maryland Gov. Marvin Mandel (D), whose criminal record was expunged following the 1987 Supreme Court decision. Mandel’s sentence had already been commuted by President Ronald Reagan after the high court refused to hear Mandel’s appeal in 1980.

Even those individuals who have yet to be sentenced in the Abramoff investigation — such as former Senate aides-turned-“Team Abramoff— lobbyists Todd Boulanger and James Hirni — could potentially revoke their plea agreements based on the court’s decision.

It is not known whether Abramoff, who is scheduled to remain in prison until December 2010, would appeal any portion of his plea agreement.

Defense Attorney Abbe Lowell, who represented Abramoff, filed a friend-of-the-court brief in one of Tuesday’s cases, but he did so on behalf of the National Association of Criminal Defense Lawyers and focused on the use of the law to pursue state lawmakers.

Loyola Law School Los Angeles professor Laurie Levenson noted, however, that distinctions made by the court — rather than merely overturning the law — could complicate any decisions about plea agreements or appeals.

“It may say that [the honest services provision is] unconstitutional unless you use a certain standard,— Levenson said. “The details will be important.—

Whatever the ultimate determination, individuals seeking an appeal or other relief would be limited to those charges under the honest services provision, Brand said.

“The only counts that could conceivably be voided would be honest services counts, were the Supreme Court to change that law … general conspiracy counts would stand,— Brand said.

Ex-Rep. William Jefferson (D-La.), who is appealing a guilty verdict on 11 criminal charges, could potentially benefit from a favorable Supreme Court ruling, but his conviction includes six counts that do not involve honest services fraud.

Among the audience at Tuesday’s Supreme Court hearing was Assistant U.S. Attorney Mark Lytle, the lead prosecutor in Jefferson’s recent trial in the U.S. District Court for the Eastern District of Virginia.