Since it began two months ago, the political corruption trial of Marvin Mandel and five other men has featured accusation upon accusation, denial upon denial. But the ultimate accusation came the other day, and it appeared to be irrefutable.

A fellow known around here as Mr. Diz, the Baltimore town crier and character of the federal courthouse, said of the trial: "It's dull, dull, dull, dull, dull."

The courtroom audience - its size and composition - tells the story, said Mr. Diz. The trial has drawn a full house only three or four times. This, despite the attractive setting (courtroom 1-A is spacious, comfortable, has excellent acoustics and no bad seats) and the inherent appeal of the case (the top public official in the state being charged with corruption).

By Mr. Diz's standards, a good trial should attract the same people back every day, not just once or twice a week, and these regulars should make up at least half the daily audience. The courtroom regulars in the Mandel trial number no more than 10. Some of them have been seen skipping out on the afternoon testimony.

"Ya just can't draw in Baltimore anymore," Mr. Diz lamented. "Sure, they filled the place when the governor was on the stand, but even that got boring after a few days. It goes on too long and people get tired of it all. May be in New York or Philadelphia they can draw crowds for something like this. But here, ya know, a lot of the oldsters have died off. The yound ones don't care."

But despite the lament of Mr. Diz, who has decided the case would have been better handled "just by giving 'em all lie detector tests and getting it over with," there is some drama in and around courtroom 1-A these days. It is a private drama being played out by people who have become quite familiar - perhaps too familiar - with one another: the lawyers, the defendants, the judge, the artists, the court reporters and the Journalists.

These are the people who are at the Mandel trial because they have to be there. Many of them have grown accustomed to the situation and find it enjoyable. Others are feeling claustrophobic and anxious to get out. All of them, over the course of two months, have become part of a subculture.

In this subculture, the attorneys appear preminent. This is partly because there are so many of them (17) and partly because they try so hard to be pre-eminent. They strut around the courthouse like roosters, the lowliest among them assuming a noble air. There are at least two ways to determine the pecking order among these attorneys.

The first test is the finger flick method. The finger flick is exactly what it would seem to be - a flick of one or more fingers. It is not a particularly subtle sign language developed by attorneys who want to say, "Come here, you, I want to tell you something," without upsetting the judge. All 17 attorneys in the Mandel trial are experienced finger flickers, but some appear better than others.

Generally speaking prosecutor Barnett D. Skolnil, Mandel attorney Arnold Weiner and William Hundley, who represents defendant W. Dale Hess, can lure someone to their seats with finger flicks. On those rare occasions when they are flicking fingers at the same time. Hundley usually prevails.

The most prolific finger flickers are the attorneys for the two Rodgers brothers: Michael Marr representing William Rodgers and Thomas Green representing Harry Rodgers III. Green is the impatient one. He flicks while moving toward the person he wants to talk with. Marr, in one five-minute span, flicked eight times without once luring someone to his side.

The other way to determine the stature of a Mandel trial attorney is to count how many journalists he attracts during a break in the proceedings and how those journalists act while chewing the fat with him. As a general rule, Weiner and Skolnik draw journalists even when there is nothing to say. Hundley usually acts as though reporters are his best friends. When interacting with these three attorneys the jounalists usually assume a relaxed posture, as though they are peers. An imaginary golf swing is effective in this situation, as is a joke about the attorney's client.

One of the reporters was furious when Mandel did not take the witness stand at the hour his attorney, Weiner, had told them Mandel would. The reporter charged that Weiner had "sandbagged" the press corps, legal jargon for holding back with an important and unexpected piece of evidence. In return, the reporter would "sandbag" Weiner by emphasizing the testimony of a witness who did little to help the defense case.

The relationship between the reporters and the defendants in the case is quite different. Mandel's conversations with the press have been limited to those for furious asponds when the television cameras catch him entering or leaving the courthouse. The Rodgers brothers and Ernest Cory have been only slightly more talkative. W. Dale Hess and Ivin Kovens have for the most part maintained an easygoing nature.

Kovens, with his silver hair and sharkskin suits, has been acting more like a television analyst - the trial's Eric Severeid - than a man who could soon face a jail sentence. He has been eager to offer his thoughts on each day's testimony to anyone willing to listen. His thoughts are buttressed by the meticulous note she takes.

Kovens' notes are neatly printed on yellow legal pads furnished to him by his attorney, Norman Ramsey. He uses two pens for the notes, one with blue ink and one with red ink. When asked what the notes were for, Kovens joked they were "bedtime reading for my wife. Later, in answer to the same question he said he was going to write a book. If that is the case, the book will be well indexed. Kovens' notes include an index of every witness and almost every name that has been mentioned at the trial.

But if there is a book to be written about the experience in courtroom 1-A, the most promising title would be: "Quotations from Judge Taylor." U.S. District Judge Robert Love Taylor has enlivened many a dull stretch of testimony with his remarks from the bench. Taylor is 77 years old. He has the accent and philosophy of a man who has spent most of his life as a "country judge" in Knoxville, Tenn.

Taylor handles the flock of attorneys with a kind disdain. He sustains objections only under the rarest circumstances and often complains that trials should not be dominated by arguments among attorneys. But even his harshest criticisms are cushioned with a light touch. Yesterday, for example, Taylor told one prosecution lawyer to stop saying "in the light of previous testimony . . ." when questioning a witness.

"If you do that down South, you'll never get out," said Judge Taylor. "Tell a man down South that he's a liar, then you better be prepared to fight, a real fight. Now, if you're prepared for that, all right. Want me to be the referee?"