With the sudden and unexpected demise of the Gary Hart and Joe Biden presidential campaigns, the role of the press in the election process once again is thrust front and center as an issue.

The candidates' supporters protest that they've seen media portrayals of their candidates that have little resemblance to the men they know. Others decry the attention to the candidates' past and private lives as opposed to their positions on the issues. Some question by what right the media set themselves up as judges of the candidates: "Who elected you?" they ask.

As if that weren't enough, Everette Dennis, executive director of the Gannett Center for Media Studies, has weighed in with an article titled "The Press as Moral Teacher," in which he states that "the media are, in fact, monitoring and enforcing American values." Now, there's a charge that will make your average reporter or editor shiver and reach for the gin bottle. Most newspersons don't want to be players in the drama, although we know that the media are as much a part of the political system as the polling places. The problem is that the media often can't just be neutral purveyors of information. Either we're charged with going too far or we have self-doubts that we did enough.

If Hart and Biden want to identify the real villains of their public immolations, they don't have to look any farther than the factors that have contributed to the weakening of the political parties. These include the New Deal, which federalized welfare programs that many urban machines had provided; television, which made it possible for candidates to bypass the party machinery; and the Democratic Party reformers who, after the 1968 convention, were determined to take the system away from the bosses in the smoke-filled rooms and open it to everyone -- the young, minorities, women, the poor.

The result is that the candidate-screening process has become public, often conducted on nationwide network television. And when the screening is perceived to be on character and morality, a red flag goes up in a lot of minds about the screening institution -- the press.

Many people misunderstood the Hart and Biden cases because they don't understand their context. Hart's womanizing and Biden's tendency to shoot from the lip were well known in political and press circles, which thus weren't as surprised as the public when the cases blew up so suddenly and dramatically. In the old days, these matters of inner knowledge used to be worked out behind closed doors. Now it's done in public, like the hangings in London in days gone by. It's far more brutal, and in many instances the results aren't nearly as satisfactory.

John Sears, who was a leading strategist for Richard Nixon in 1968 and for Ronald Reagan in 1976 and 1980, has had some experience in these matters.

"Twenty or 25 years ago when we didn't have so many primaries, the press didn't have to play as active a role as it does today because a lot of people who might think of running for president were really screened out by the party leaders and we never knew the exact reasons," he told reporters recently. This process worked to screen out Sen. Estes Kefauver, another noted womanizer, in 1952, Sears contended.

He said that those same Democratic Party leaders whose support John F. Kennedy needed in 1959 and 1960 had probably gone over the stories of his womanizing with him and "at least gained his verbal assurance or something that he'd toe the line a lot better, and if he'd show that he was single-minded about the office and that he knew this was serious business they agreed to go ahead and support him . . . . Now nobody has the power to make such a conversation meaningful."

The party leaders also can often interrogate the candidates more effectively on issues. Sears recalls accompanying Nixon in 1968 to seek the support of Billy Meehan, the Republican boss of Philadelphia.

"Meehan says, 'Hey, Dick, what are you going to do about this Vietnam War?' " Sears recalled. "Nixon started to say the same thing he'd said in public, and Meehan says, 'No, no, no. I don't mean that s---! I mean, what are you going to do?' And Nixon says, well, when he got in he was going to try to get the troop commitment down, begin to pull the troops out and make the Air Force and Navy carry more of the load so he could make a settlement. I never heard him ever say that in public, but that's what he did. You couldn't lie to Billy Meehan because he knew enough about the game to know what was baloney."

Meehan also forced Nixon to tell how his campaign could help win the 35 to 40 percent black vote Meehan's candidates needed to win in Philadelphia. "Years later, I was out with Ronald Reagan, and Walter Cronkite asks him how he was going to get black votes and Reagan says, 'I'm going to get them the same way I get white votes' and that was the end of that," Sears recalled. "If anybody had ever said that to Billy Meehan, that would be the end of them with Billy Meehan. Cronkite knew better but he couldn't follow it up."

No one advocates a return to slate-making in smoke-filled rooms, even if it were possible. But a partial restoration of a more private candidate-screening process by party leaders would certainly be easier on the candidates' nerves, and probably the press' and the voters' as well. The writer is a political reporter on The Post's national staff.