One legal expert says President Clinton's greatest problem following the explosive report from special prosecutor Kenneth Starr is the allegation that he abused his presidential powers. That shows a calculated plan of wrongdoing rather than an embarrassed married man's effort to cover up an affair.

But a political scientist says Clinton's alleged attempts to obstruct justice will hurt him the most because Americans will be less likely to forgive trying to get friends to lie.As Americans are buzzing over the torrid details of Starr's 445-page report, legal and political experts are discussing what will happen next in Congress.

Perjury, obstruction of justice and witness tampering are all serious crimes, but the allegation that Clinton abused his presidential powers is perhaps the most powerful, says Paul Cassell, a University of Utah law professor and former federal prosecutor.

Abuse of presidential power was one of the three articles of impeachment lodged against former President Richard Nixon, who resigned in disgrace in 1974.

"It has a Nixonian flavor to it that will not bode well for President Clinton," Cassell said. "That charge is not susceptible to the same defense as the others are."

"The defense of the others is that this was just sex and everybody lies about sex," Cassell said. "Maybe, maybe not."

Cassell suggested that Congress might excuse a man's lies about an extramartial affair to save embarrassment to himself and his family.

But for a president and his employees in the White House to wage a seven-month effort to deny misconduct could be seen as much more calculated and less forgivable.

Even when given a chance to come clean as late as August during his grand jury testimony, Clinton lied then, according to the report, which would be perjury yet another time and that could prove to be damaging, Cassell said.

"I think this charge is more serious. This is not a heat-of-passion situation or a covering up of a heat-of-passion situation. It is a concerted, deliberate, long-term, ongoing effort which shows much more premeditation than some of the other allegations," Cassell said.

This charge, more than the others, is what could erode Clinton's support among Democrats.

And it was the loss of support from Congress - particularly Republican leaders - that ultimately forced Nixon to resign.

But Richard Davis, associate professor of political science at Brigham Young University, disagrees.

He finds the abuse of power allegation to be the weakest and thinks the obstruction of justice charges carry more weight.

"I'm talking in the realms of politics. The Constitution is very vague about what impeachment means and never defined what constitutes high crimes and misdemeanors," he said.

"This is really political in nature rather than legal because it's the political institution that has to make the decision," Davis said. "If it was a trial leading to a conviction then yes, the legal issues would matter. But the Congress isn't going to make a decision primarily based on a legal matter - they're going to make it on politics and what the American public response to this is.

"My sense is that the American public's response will be: `We've heard this before,' " he said. "I think the public is less likely to forgive if the president seemed to go out of his way to get other people to lie for him."

Davis also noted that a quick review of Starr's report lists no Clinton wrongdoing in the Whitewater land deal in Arkansas that prompt-ed the investigation in the first place. Instead, the report relies almost entirely on former White House intern Monica Lew-in-sky's version of events and the relationship between a woman who is young, but nevertheless an adult, with a married man.

"It was a consensual relationship. She was certainly doing wrong as well. Secondly, she's a known liar," Davis said.

The dirty details in the report will appall many Americans, Davis said.

"People are going to say, `It's disgusting,' which it is. However, it's important to remember this is an accusation. Is it necessarily true? We don't know. We probably never will know unless he actually confirms it."

Another problem for Congress, Davis said, is that many of its own members have skeletons in their closets and if Clinton's personal life is fair game, then so are their lives.

Recently, U.S. Rep. Dan Burton, R-Indiana, admitted having an extramarital affair and a child out of wedlock. And U.S. Rep. Helen Chenoweth, R-Idaho, also admitted having an affair with a married man when she was single.

Davis speculated that most mem-bers of Congress wish the Clinton mess would just go away.

If Clinton resigned, it would save the nation from an impeachment trial and a literal airing of dirty laundry, he said. Republicans can't back down because their constituents are livid with Clinton. Democrats want this over fast because it could hurt them in the coming elections.

In Nixon's case, the House Judiciary Committee began impeachment hearings against him in October 1973 and by July 1974 voted to recommend three articles of impeachment against Nixon.

The first article charged that he obstructed justice by delaying the investigation of the botched burglary of Democratic Party headquarters at the Watergate Hotel in 1972, as well as hiding the identities of those who ordered the break-in.

The second article alleged that Nixon abused presidential powers.

The third alleged that he disobeyed subpoenas.

There was no impeachment trial because Nixon resigned Aug. 9, 1974.