One of the more interesting contests going on in Washington this summer has been between the comic strip "Doonesbury" . . . and real life. Each has been providing its version of the House ethics committee's inquiry into the Korean lobbying scandal, the dispensation of boodle to members of Congress by the unlovely government of President Park Chung Hee. And each has yielded up insights. The question is which - the cartoon fiction or the bizarre reality as presented to TV and the press - offers the attentive observer a better understanding of what's going on. I have an awful feeling that, at the moment, anyway, Doonesbury is ahead.

This cannot be much comfort to those of us who earn our living cranking out copy that begins: "House ethics committee chairman John Flynt (D-Ga.) said yesterday . . ." But there it is - further evidence, if any were needed, that there is something about the political life of the '70s that leads itself to fiction. Never mind that the fiction isn't always up to the restrained any murderous wit of Doonesbury, the phenomenon could use some explaining.

If you doubt that the trend is there, only consider some of the improbable entries into the political novel-writing field. Agnew and Ehrlichman, whose novels were published last year; William Safire, the former Nixon speechwriter and present New York Times columnist, whose absolutely gripping White House thriller, "Full Disclosure," has made the best-seller list; CBS's Marvin Kalb, who has a novel about a Kissingeresque figure scheduled for fall; Ben Wattenberg, the political analyst and statistician who is now co-author of a novel about a death struggle between a President and his Vice President; Herbert Stein, the former chairman of the Council of Economic Advisers - not exactly a hotbed of Jackie Susanns - who has collaborated with his son on a thriller in which the villain is not a burning high rise or an insatiable shark but (what else?) a voracious and uncontrollable inflation.

There's plenty of melodrama here. Power plays, death, sex and Russians are the stuff of which this literature tends to be made. Hideous things routinely happen. Safire's President has been blinded in an assassination attempt in the Soviet Union. Agnew's Vice President becomes the tool of a foreign conspiracy. Ehrlichman gives us a mortal conflict between a President and a head of the CIA. Wattenberg's publisher tells us with pride that has novel has been described as the "blueprint for a coup." There is endless carrying on in bed, in White House closets - just about any place will do - and endless maneuvering and intrigue. Generally it is taking place at a moment when the world as we know it is about to be destroyed.

Not surprisingly, given their pot-boiling nature, some of these books stand to make a huge amount of money. Safire's paperback rights alone sold for $1,375,000, admittedly better than others can expect to do but, nonetheless, a measure of golden possibility. So at the outset, without trampling on anyone's artistic pretensions, but without getting too naive about it either, we can say that one explanation of the new descent into literature is probably money. One just has to assume that if economist Stein's novel takes off, for instance, it's going to earn him a better return than did say, an earlier work called "The Fiscal Revolution in America."

A second motive is also clear: For some of our new political novelists, at least, the "fictional" form is the only one that permits them to say certain things without getting in trouble with the people they have worked with. They aren't quite acountable for what they say and they can suggest certain things - as Ehrlichman did about Richard Helms - without ever quite having said them.This fiction, for all its melodrama, tends to be regarded as thinly disguised truth. And of course it also conveys a great deal of impersonal true information concerning things, such as, for example, how many buttons there are on the telephone that the novel's hard-pressed hero intends to use to blow up the world.

Nevertheless, when you have said this you still haven't accounted for the whole of the writer's impulse, nor for the evident interest with which these books are vacuumed up by the reading public. I think both have a lot to do with all the astonishing, squalid, funny, infuriating and - ultimately - predictably human things that the public has been learning about its elected leaders and its governmental processes over the past decade or so. Sometimes I myself indulge a fantasy that is half hope and half expectation that the era will close with an operatic finale in which everything, especially the interconnections, will be explained - in song - by a thunderous chorus that includes all the folks who have given us such a turn in recent years. There they will be standing arm in arm on the stage, singing out the meaning of it all; Dita Beard, Wayne Hays, Howard Hunt, Prince Bernhard . . .

You get the idea. It is that knowing what we know, the old explanations of both political theory and political behavior just won't do. I'm not great friend of so-called psychohistory or of much that's known as the "new journalism." Except as practiced by a very few people, both seem to me in continual danger of sinking into a kind of irrelevant, trivial, catty and psychologically pretentious interpretation of our politics, and - even worse - or confusing it with analysis. But I can surely understand how both came to supplant, as credible interpretations, the old, straight-faced, bloodless, civics-lesson baloney they passed as a plausible account of what was happening - and why - in Washington.

The new novelists, some of whom are pretty good and some of whom are positively execrable, at least are writing clearly labeled fiction. But they are also trying to provide a kind of gloss on formal, official proceedings and to indicate the central truth about this place, which is that the chairman - whoever he is - of the committee - never mind which one - did not do that thing, strictly and clearly for some ideological or partisan purpose. Five will get you 10 that there was also at play a personal ambition, a head cold, a desire to catch a plane, a trade-off, a girl - or some combination of all the above.

We could do worse than to think about our politics that way, as a corrective - and to a degree. But a new illusion will come if we replace the old highfalutin shams will the novelistic plot line as an explanation of official behavior. No more than they have an irreproachable political explanation do most Washington performances have a dramatically consistent cast of characters or a definable beginning, middle and end. We could end up trading one misconception for another. But to be frank with you, it's too hot to worry about that now. Summer is here and so is the new literature in all its varied splendor and squalor. Read some.