When it comes to government and politics and the media, one of the most sacred doctrines is the doctrine of fairness.

It's not just an expectation, all concerned and the public the participants in this arrangement serve, demand that fairness be observed. Without that fairness, all that is communicated is suspect.

It is for this reason that we are terrifically disappointed with the National Broadcasting Company, which intends to air a television docudrama about Congresswoman Carolyn McCarthy during the May sweeps period.

The movie, which is to star Laurie Metcalf, of Roseanne fame, as the congresswoman, and Mackenzie Astin as her son Kevin, is being co-produced by Barbra Streisand and Cis Corman, and directed by multiple Emmy winner Joseph Sargent.

The little that has been released by the network about the picture, which is as yet untitled, indicates that it will cover the congresswoman's life from the night LIRR gunman Colin Ferguson cut down her husband and gravely injured her son, to the night she won election to Congress in 1996. In short, the period during which the local media here on Long Island elevated Mrs. McCarthy to near saintly status.

To portray the congresswoman in this light, given, particularly the fact that she will stand for re-election just six months later, seems appallingly unfair to whomever decides to challenge her for this post.

Will we be seeing a glowing two-hour portrait of Dan Frisa on NBC if he is chosen by the Nassau County Republican Committee to run? or of Msgr. James P. Lisante, if he decides to run? or of any other candidate, Republican, Right-to-Life or Independent who may challenge her?

Fat chance.

What we will see is a Hallmark Card portrayal of an individual, with all her rough spots - her marital problems, her lackluster career once in office - either ignored or downplayed dramatically.

What we'll see, most likely, is Carolyn McCarthy, an outspoken opponent to assault weapons. What we won't see is the fact that she has proposed not one piece of anti-assault weapons legislation since she's been in office.

What we'll see is a woman running as a Democrat - a party for which Barbra Streisand has a well-publicized affinity - but likely not the fact that McCarthy never changed her party affiliation and remains, to this day, a registered Republican - a political opportunist who ran as a Democrat only after being rejected as a candidate by her own party.

If NBC does indeed run this movie prior to the first week of November, it will, in effect, be endorsing Mrs. McCarthy.

Though it will likely try to dodge the issue by saying that the movie is a product of its entertainment, rather than news division, this much is clear: if this docudrama is in fact shown this spring, NBC will have tainted the local 1998 congressional race terribly and done us all irreparable harm.