Grand finale tonight for Bill Moyers's Constitution series

Moyers: In Search of the Constitution - 1987, Part 10 PBS, tonight, 8-9 p.m. (check local listings for day, time, and repeats). Producer/director: Elena Mannes. Executive editor: Bill Moyers. Bill Moyers's celebration of the 200th anniversary of the United States Constitution has turned out to be a glorious surprise party.

This 10-part series (11 in areas where an extra interview with Attorney General Edwin Meese was inserted on May 28) has been filled with unexpected insight and exciting revelation about the document America's Founding Fathers bequeathed to the world.

In this final segment, Moyers once again illuminates 1787 attitudes in the light of 1987 mores. He discovers and explores many common links and hidden meanings as he interprets that glorious document and its everyday impact upon contemporary society.

Current issues that the original framers of the Constitution could not possibly have anticipated seem nevertheless to be covered, if not in the letter, at least in the spirit of the document. Mandatory drug testing, computer technology, and nuclear warfare are three such contemporary problems Moyers examines in detail, using interviews with average citizens as well as experts.

Ira Glasser, executive director of the American Civil Liberties Union, takes the side of workers at the Bath (Maine) Iron Works who object to employee drug testing.

``They're picking people they want to get rid of,'' says a worker. ``It's like you're guilty until proven innocent.''

``If you don't have criminal evidence as the standard for allowing searches,'' Glasser says, ``searches will be done based on politics.''

In response, a spokesperson from the company says: ``As a deterrence, I can't think of any more positive message to send to high schoolers and college kids these days than: `If you want to stay in Maine, if you want to work at Bath Iron Works, you're going to have to take the test.'''

Moyers prompts viewers to consider whether or not mandatory testing is a violation of the Fourth Amendment's protection against illegal searches of the home and place of business.

The growth of computer technology, which allows for widespread access to personal information, is another contemporary privacy issue the writers of the Constitution could not have anticipated. Once again, Moyers urges viewers to consider whether Fourth Amendment prohibitions against searches without warrants extend to private data stored on computer discs?

And then there is the especially relevant question of the War Powers Clause, which limits a President's right to declare war by requiring consultation with Congress. Moyers points out that since World War II there has been no declaration of war by Congress preceding US military action in Korea, Vietnam, Grenada, and Libya.

Vice-Adm. William Ramsey of NORAD, the North American defense shield, tells Moyers that the President might have to make a decision to strike back against an incoming hostile missile in 5 to 10 minutes. Can Congress be in on that decision, Moyers asks by implication?

Obviously many contemporary issues are not specifically mentioned in the Constitution. How can the American democracy cope with them?

The answer, according to Moyers, lies in ``the moral commitment to liberty and dignity, the supremacy of the spirit of the law.

``Like a soft, steady backlight,'' he says, ``the spirit of this Constitution illuminates the letter on the page. No issue we face today, no matter how new or threatening, is unapproachable in its glow.''

``Moyers: In Search of the Constitution'' has made for timely television; so much of what Moyers has to say is relevant to events occurring at this very moment. But it is also timeless television; his penetrating perceptions constitute an electronic legacy to democracy.

Moyers says: ``We have revered and debated the Constitution, honored it and criticized it. We even fought a bloody civil war over it. But we have lived with it. We are still living with it today. Still debating it. Still in search of the Constitution.''

American television audiences are fortunate that Moyers made the switch from CBS, which was too concerned with audience numbers to allow him to carry on his search there. PBS and General Motors, which gave him the opportunity to go ahead with the series, should be applauded for their public spirit and foresight.

Now, how about a repeat of the whole series before this anniversary year is over?