THE SILLIER SIDE of psychiatry shone through the diplomatic haze last Friday, when the State Department released an Air Force psychiatrist's report on a would-be Soviet defector. In several thousand equivocal words, a scientific charlatan shrouded hokum, pure and simple, in the mantle of medicine.

At the center of the maelstrom stood one Miroslav Medved, a 25-year-old Ukrainian seaman who on Oct. 24 jumped from a Soviet freighter into the Mississippi River near New Orleans. Immigration officials questioned Medved through a Justice Department interpreter, via telephone. According to the officials, Medved said he did not want to defect. Later, the interpreter said that they had misunderstood.

Immigration officials returned Medved to the freighter a few hours after he had jumped. Or at least they tried: along they way, he jumped into the water again. Seamen from the freighter picked him up and carried him back to the ship.

Enter the shrink. On Oct. 28, the State Department removed Medved from the freighter and asked Air Force psychiatrist Maj. William M. Hunt III to interview him. Hunt conducted two psychiatric interviews with Medved over 12 hours. Then Medved went back to his ship and Hunt back to his typewriter.

Hunt writes in his report that Medved "rather impulsively decided to jump ship and seek political asylum, but not likely due to any extremely strong political or moral convictions, rather more consistent with his immature, impulsive, action-oriented personality style." Now there's an interesting conception of human nature. People don't act because of convictions or conditioning or complexes, but because of "action-oriented personality styles." Which makes everything crystal clear: Medved acted impulsively because he is an impulsive person.

Later, Hunt discusses Medved's "premorbid personality." Defection is portrayed, though not in so many words, as a kind of mental illness, complete with fancy name and symptoms. "The best diagnostic formulation," Hunt writes, "is that the individual suffered an adjustment disorder, with situationally related depression, agitation, and a suicidal attempt/gesture at one point and hypomanic excitement later." Hunt explains that the "suicidal attempt/gesture" resulted in a gash on Medved's forearm that the Soviet freighter's doctor said was self-inflicted.

LET'S TRANSLATE. Medved didn't like his life in the Soviet Union, so he tried to defect ("suffered an adjustment disorder"). When his defection attempt failed he was disappointed ("situationally related depression"). Trying to escape again--or as punishment for trying the first time--he was beaten ("agitation and a suicidal attempt/gesture"). He fought back ("hypomanic excitement").

Hunt is either extremely naive or extremely disingenuous. The Soviet doctor told the psychiatrist that Medved had "himself inflicted the laceration on his forearm...[during] a brief psychotic reaction." But in the report, Hunt asserts that Medved was "clearly not psychotic [his italics]"--which would appear to make the Soviet doctor's explanation somewhat hard to believe.

The Soviet doctor also told Hunt that Medved had been given neuroleptics--dopamine-blocking tranquilizers. Hunt writes that the doctor said that these drugs "were commonly used in his country to treat schizophrenics." In other words, crazies like Andrei Sakarov.

On the whole, Medved is a lucky man. Hunt was "strongly entertaining the possibility of a major affective disorder, namely Bipolar Disorder or Manic Depressive Illness." But the mood passed. He "currently considers it more likely that [Medved] had an immature personality." Even "if he did suffer from Bipolar Disorder, then his jumping and defection attempt would likely have been secondary to the illness, and thus, still impulsive in nature."

Strangely enough, even after all his scientistic circumlocution, Hunt concludes that Medved was "clearly competent, to the extent that any Soviet citizen in his position could be, to make a decision in regards [sic] to defection."

And when Medved was interviewed a second time by State Department officials, he denied that he had ever wanted to defect. And not wanting to jeopardize U.S.-Soviet relations on the eve of the first superpowwow in six years, Administration officials decided not to press the issue.

The U.S. is apparently about as objective in determining who is mentally ill as the Soviet Union is. Whether or not you have mental problems, it just doesn't pay to want to come to the U.S. when it doesn't want you.