Two months ago, I wrote about the imprisonment by the Air Force of 2nd Lt. Joann Newak. The young woman--25, intelligent, a graduate of Marywood College in Scranton, Pa.--was given six years at hard labor in Fort Leavenworth, Kan. She began her sentence in June.

Newak had been found guilty by an Air Force judge of marijuana, sodomy, amphetamine and conduct-unbecoming-an-officer charges. A few days ago, three Air Force appellate judges upheld the decision.

Something is ludicrously odd about this case, and I recall first sensing it during the appeals hearings in October. Newak was having her day in court by having another day in prison. Instead of being free while her case was under appeal, which is routine in civilian courts for offenses of far greater severity than Newak's, the lieutenant was locked away in Leavenworth. Should a reversal eventually come through, the Air Force presumably will give Newak a cheery "sorry about that."

The oddity expanded to bizarreness when the disparity between the harshness of the sentence and the mildness of the so-called crimes was examined. I say so-called not to be arch, but because New York--the state in which Newak was stationed--does not prosecute, much less imprison, its citizens for minor marijuana involvement or for their sexual preferences.

Newak was a recreational user of pot who occasionally shared the substance among friends at her off-base apartment at Hancock Field, near Syracuse, during off-hours. Her crime of "sodomy" demands another so-called. Newak was involved in a personal relationship with an Air Force woman. Lesbianism is not a crime under the military code, so the Air Force, with a stab at unisex justice, nabbed her for sodomy.

The amphetamines, equally alarming to the Air Force, were discovered to be diet pills when tested in a lab. Newak's offense was to think the pills on her dresser were illegal.

As the Air Force carried Newak off into the wild blue yonder of military justice, it appeared at first that this was another example of martial excess. What cost overruns in Air Force bombers are to rational defense, sentences to six years at hard labor for nonviolent first offenses are to sensible justice. In the past four years, an Air Force dragnet has been spread wide to catch more people.

On the last day of 1978, there were 176 Air Force people in prison. By June 1982, with only a perceptible increase in the ranks, the prisoner roll reached 692.

An Air Force spokesman explained this surging increase of nearly 400 percent as "a change in administration and stricter approaches to discipline." He didn't mention that with more young people seeing the unemployment lines and turning in last resort to the armed services for jobs, the new harshness is a way of announcing to recruits that the military is toughening its standards.

Jailing decent and up-front young women like Joann Newak is a dubious way of toughening anything. The standard it leads to is a double standard, one that lays bare the extremes that the separation of military and civilian justice systems can lead to.

The argument of many in the military--at least those who think Newak got what was coming--is that the Uniform Code of Military Justice applies to everyone in the armed services--24 hours a day in all places--and that the Supreme Court recognizes the need for this separate legal system. In theory, fine. But where is the line between a separate law and law-unto-itself? Are constitutional rights meaningless upon putting on the uniform? If anything, with the military priding itself on being the first line of defense in defending the constitution, those rights ought to be more honored, not less. Instead, the extremes are being honored.

Those extremes didn't bother the three Air Force appellate judges who ruled that Newak's sledgehammer sentence was appropriate. In one opinion, Lt. Col. Edward Miller concludes by suggesting that not only are the civilian and military judicial standards justifiably different but also that the military's is, by far, superior: "Had the accused (Newak) been tried on these identical charges in a civilian court, which would probably have been unfamiliar with the laws and traditions developed by the military during its long history, it is likely the court would not have had full capacity to recognize the complete impact of damage to the national security resulting from such conduct on the part of a commissioned officer."

So that's it. A few puffs of pot in your living room, some no-no friendship with another woman, and before you can say Air Force Dense Pack, "national security" is dealt a first-strike hit.

Faith Seidenberg, the Syracuse lawyer who is defending Newak for no fee, is bringing the case to a higher military appeals court that has three civilian judges. The National Lawyers Guild, and other groups, have joined the appeal. A new test case, involving basic constitutional questions, is developing.

Meanwhile, when Joann Newak writes to me, and when I answer, the letters both ways are opened, read and stamped by her jailers. In the mind of the military, some correspondence between citizens is also a threat to national security.