Last spring, after President Reagan's televised address to the nation on his proposed 1987 defense budget, the networks provided the traditional response time to the Democratic Party, represented in this case by House Majority Leader Jim Wright. ABC News, however, varied the response format considerably by also giving rather a lot of air time to Vladimir Posner, who is often described as a "Soviet journalist" but who is, of course, a functionary of the Soviet state. ABC's own John McWethy noted, after Posner had called the president a liar in so many words, that Posner's appearance reflected the openness of American society and thus highlighted, by contrast, the closed state of affairs in the USSR. Other reactions weren't quite so charitable. The president wondered aloud what was going on, while White House Communications Director Patrick Buchanan queried, in a publicly released letter to ABC News president Roone Arledge, whether, on the ABC/Posner model, the British should have allowed Dr. Goebbels to respond to Churchill's speeches in favor of British rearmament.

Since that initial flap, Mr. Posner has continued to make frequent appearances on American TV (he recently described himself to Jane Pauley as "a political observer for Soviet television and radio"), as have Georgi Arbatov of the Soviet Institute for the Study of the U.S.A. and Canada, and Gennadi Gerasimov, spokesman for the Soviet foreign ministry.

About which a few points are in order:

American networks have a journalistic responsibility to identify accurately both guest commentators and sources. To call Vladimir Posner a "journalist," or, more subtly, to use him on a broadcast in a manner that suggests he is an independent commentator, perhaps Radio Moscow's answer to Bill Moyers or George Will, is to fail to meet that responsibility. (The networks aren't the only ones who fall into obscurantist euphemisms in dealing with the Soviets, of course. Congressional exchange groups who describe their Soviet counterparts as "parliamentarians" are just as bad. Why not simply describe them as members of the Supreme Soviet, which is factual, rather than suggesting they have some deliberative or legislative parliamentary functions as we normally understand these terms, which is an inversion of fact?)

TV journalism, given its critical importance in American political culture, has a particular moral stake in accuracy. ABC's concession last spring was that it probably kept Posner on the air too long. But that was hardly the point, was it? The point is that a source be accurately identified in a way that makes clear, in this case, his lack of independence and his relationship to the Soviet government. One might also wonder why, in the course of the eight or nine minutes Posner was on the air, he wasn't challenged on some of his assertions, particularly on such howlers as his claim that the Soviet Union wasn't doing research on strategic defense systems.

On the other hand, there is no reason why Soviet apparatchiki such as Mr. Posner, Dr. Arbatov, and Mr. Gerasimov shouldn't be brought onto American television to make their case—provided that they're correctly identified and that they're given the same kind of grilling to which our own political leaders are subject. There are occasional breaks with this pattern of unaccustomed gentility from our TV inquisitors. When Mr. Gorbachev once claimed, in a baldfaced lie, that there was no Jewish emigration problem in the USSR, Dan Rather took him on, firmly and respectfully. But Mr. Gorbachev's minions, such as Posner, Arbatov, and Gerasimov, are subjected to nothing remotely resembling the skepticism with which the Fourth Estate treats the president and members of Congress.

As satellite television technology continues to expand, "spacebridges" between U.S. and Soviet TV sets will increase exponentially. In the open competition of political ideas, we have nothing to fear. But the Posner flap suggests that even our most sophisticated broad casting organizations haven't begun to come to grips with the problems inherent in this process. The choice shouldn't be between no debate and unchallenged mendacity by misidentified "commentators." The heirs of Edward R. Murrow can do a lot better.