Continued from page 1

And earlier this week, the department announced it would not seek charges against former House Majority Leader Tom DeLay, the Texas Republican who had been seen as the most high-profile and powerful target of the Abramoff investigation.

Carl Tobias, professor at University of Richmond School of Law, said he does not necessarily see any common threads in the cases that have vexed the Justice Department lately, but said its troubles may say something about the nature of politicians who end up in trouble.

“It could be that much of what they do is close to the [legal] line,” Mr. Tobias said.

Barry J. Pollack, a white-collar defense attorney with the D.C. firm Miller & Chevalier agreed, adding that in white-collar and political corruption cases, there are “a lot of gray areas.”

“The line between what is distasteful conduct and what is illegal conduct has never been particularly clear,” he said, adding that the department has become more aggressive in going after ambiguous cases.

But it’s not as if the Justice Department has not been without victories recently: Last summer, former Rep. William Jefferson, Louisiana Democrat, was convicted on 11 of 16 counts in a case made famous by the $90,000 he stashed in his freezer. Jefferson was sentenced to 13 years in prison, but was allowed to remain free pending appeal.

Blagojevich will also remain free despite his conviction for lying to FBI agents when he said he kept his political campaigns and official duties separate and he did not keep tabs on who made campaign contributions.

Mr. Pollack said Blagojevich’s conviction is typical of some high-profile cases in which no crime is ever proved, except that the defendant lied during the investigation.

Two other Justice Department cases are parallel examples; the case of homemaking celebrity Martha Stewart, convicted of lying to authorities as part of an insider-trading case, but never convicted of actual insider trading, and former vice presidential aide I. Lewis “Scooter” Libby Jr., convicted of lying to a grand jury investigating who leaked the identity of former CIA operative Valerie Plame, though no one was ever charged with actually revealing Ms. Plame’s identity.

“It’s long been true in Washington in political scandals that people almost always get in trouble for the cover-up rather than he underlying event, and that’s often true in criminal law as well,” Mr. Pollack said. “”It is often easier to prove an after-the-fact lie than the underlying conduct was illegal.”