So far, the most novel feature of the 1988 presidential campaign has been the swiftness of its fatalities.

First Gary Hart and now Sen. Joseph R. Biden Jr. (D-Del.) have abandoned their candidacies amid anger, frustration and bad publicity -- and each did so months before any voter had a chance to ratify or overrule the unsparing portraits drawn of them by newspapers and television.

"We were watching the media create a man we didn't know," Thomas Vallely, a political aide to Biden, said last week as he explained why his candidate felt he had nowhere to go but out. "And there was nothing we could do to change it."

Such trials by media ordeal -- wherein a candidate's lapses of judgment or behavior are seized upon by the news media as symbols for some disqualifying flaw of character -- are hardly new to presidential politics. They have become, over the past two decades, a standard means of pruning the field, of "getting rid of the funny ones," as one 1988 campaign manager described it.

What's different this time is the timing. In the past, this winnowing hadn't begun until the start of primary and caucus voting, and the voters served as an appeals court from press judgments. The lone exception until now came in the 1968 campaign, when Michigan Gov. George Romney (R) was fatally wounded by the coverage of his statement that he was "brainwashed" about the Vietnam war. He staggered on for months before pulling out of the race on the eve of the New Hampshire primary.

But now, the sequencing has been thrown out of kilter -- as if, in a football game, a quarter of sudden death were being played before the opening kickoff. Or, to quote columnist Mike Royko, it's not so much a campaign this time around, it's a demolition derby.

Why so?

The short answer is that candidates, as they start their campaigning earlier and earlier, expose themselves to the perils of press scrutiny sooner and sooner.

The more complicated explanation is that the nature of the scrutiny has changed. It's grown closer, harsher, quicker, deadlier.

Reporters and editors who used to be ambivalent about playing the dicey, subjective role of "character cop" toward potential White House occupants now tend to be much more assertive about their obligation to provide a first line of defense against "another flawed presidency."

"It always sounds sanctimonious to say it's a public service, but I honestly think that's what it is," said Craig Whitney, Washington bureau chief of The New York Times, which helped begin Biden's downfall with a front-page story about Biden's lifting of lengthy passages from British Labor Party leader Neil Kinnock's speeches. "Would people rather not know these guys' character flaws?" Whitney asked.

"The media has a major role to play in helping people figure out who these candidates are," said Sanford Unger, dean of the School of Communication at American University. "The fact that this scrutiny is occurring before the campaign really begins is a blessing. It winnows the field, helps people concentrate on real possibilities."

Ralph Whitehead, a professor of journalism and public policy at the University of Massachusetts, and a sometime consultant to Democratic candidates, theorized that journalists' zeal this time may be a compensation for regrets about not hammering harder at flaws they saw in candidate Ronald Reagan in 1980.

"You almost get the feeling that the press thinks they better go after these guys while they're all still three feet tall," he said, "because they found with Reagan, once he got the megaphone of the White House, they couldn't touch him for a long time."

Greg Schneiders, a Democratic campaign consultant, said: "I think we have got a unique situation in 1988 because the {Democratic} candidates are unknown to the public, but reasonably well-known to the insiders -- the press, members of the House or Senate, staffers, consultants, pollsters, fund-raisers . . . . They've got some idea of where to look for a failing and when they find some evidence, they're all over it."

Thus, it became a standardized sentence in stories about Hart last spring that the womanizing reflected a pattern of recklessness and need to flout established rules of behavior; and in stories about Biden that the plagiarizing reflected a lack of intellectual discipline, a tendency to think with his mouth. Columnists, editorial writers, commentators probed these traits more deeply. What was striking about coverage in both instances was its virtual unanimity; there was little or no dissent from the proposition that small lapses stood for major flaws.

These cases suggest that the frequently heard cliches about the passing of the old system of peer review -- wherein party bosses would veto potential presidential candidacies based on their private assessment of character weaknesses -- miss the mark. A new peer review operation has grown up, manned by the new powers in a media-oriented democracy. The judgments of these new insiders may not be as automatically lethal as those of the old bosses, but they can surely be more humiliating. That's because, as Duke history professor James David Barber notes, "What used to be done in smoke-filled rooms is now done in light-filled rooms."

Barber is one of several prominent scholars of the presidency who actively encourages reporters and editors to don the uniform of the character cop. Nonetheless, he worries that in the two celebrated cases this year, the press has been peering through the wrong magnifying glasses.

"There's got to be something more to this than working your way through the Ten Commandments -- adultery, false witness, etc.," he said. The trouble is, as Whitehead observes, the press is drawn toward simple, dramatic story lines, and if they spin out as morality plays, so much the better.

Another danger in this kind of scrutiny is that it invites manipulation by the insiders who understand best how the process works. Shortly after Hart was forced out of the race, for example, false rumors circulated among political insiders that a story was about to break about an extramarital relationship involving Vice President Bush. In that instance, no one in the press bit -- although Bush campaign headquarters grew so nervous that it eventually had one of Bush's sons issue a denial.

On the other hand, the initial Biden story was brought about by an "attack video" that was put together by someone working for a rival Democratic candidate, dramatically juxtaposing Biden's words and gestures with Kinnock's.

"Biden was one of the first victims of the video revolution," said political analyst William Schneider.

He added that the Biden downfall involved more than that, of course. The first Biden plagiarism revelation was followed by another and then a disclosure about his inflating his academic credentials, until he was killed by a collection of small cuts.

Schneider said he is troubled that the process has been so thrust forward in time as to leave out the voters -- and he foresees the potential for a backlash. A Washington Post-ABC News Poll completed last week, just before Biden dropped out, showed that of those Democrats familiar with the controversy roiling around him, 57 percent wanted him to stay in the race and 41 percent thought he should get out.

Those numbers reflect what Biden's field staff in Iowa was hearing. At campaign headquarters in Des Moines, there was an improvised "Bite Back!" poster on the wall. And until the eve of Biden's withdrawal, state cochairman Lowell Junkins was advocating that Biden stay in the race.

Biden chose not to pursue that course, in part because he had a peculiar vulnerability to the insider screening committee. He entered the race without any national base or reputation. When the damaging portraits of him began to be drawn, all he could fall back on was a small cadre of personal and campaign loyalists. Under the circumstances, they lacked the clout or credibility to stem the tide. Hart, although he gained celebrity and name recognition from his 1984 bid, found himself in much the same condition. None of his peer group spoke up for him. And since there were no primaries or caucuses on the horizon, there was no way to take his case to the voters.