A message against vigilante justice that lands with a thud

Hollywood often has trouble putting its heart and its mind on the same wavelength. Good intentions are one thing. Intelligent results are quite another.

The Star Chamber is a textbook example. It's a muckraking movie in the grand style, with a capital-T Theme and oodles of righteous indignation. But the treatment is so thudding, and the style so ham-handed, that credibility bites the dust long before the bad guys do.

Michael Douglas plays a California judge. Every day he faces a parade of evildoers, each more wicked than the last. But he has to let them all go - even the ones who confess! - because of flaws and flukes in the legal code.

He gets particularly peeved when two of the worst villains go free, on a technicality so small I'm not sure it's even there. But he's not the only one upset over all this. There's a whole club of peeved judges, in fact, and they've decided to ''do something'' about the situation. What they do is ''review'' cases, condemn the crooks without shilly-shallying over details, and send an executioner to carry out their sentences.

For half its length, ''The Star Chamber'' coaxes us - bullies us, even - to root for this secret court. Its members are dapper, educated, and worried about ''what's gone wrong with the law.'' By contrast, its targets aren't just criminals, they're monsters: child-rapers, old-lady killers, and the like - bug-eyed from dope, forever foul-mouthed, and never, ever decently shaved. Even bleeding hearts in the audience may find themselves biting hard on their popcorn and muttering, ''Throw the book at 'em.''

Then, without warning, the movie goes liberal. Two of the bug-eyed monsters aren't guilty, we find out, yet the secret court has already condemned them. Stricken by conscience, our hero visits their illicit-drug factory and while they beat him up for his trouble, he gallantly warns them to flee for their lives.

By the last scene he's turned against the court altogether and plans to blow the whistle on it. But will this help? If monsters all slip through the law's grasp nowadays, surely the smoothies of the ''star chamber'' can spring themselves in time for a sequel.

There's no question about the movie's moral: Vigilante justice is bad, even when it has lots of money and wears a three-piece suit.

I wonder, though, if the filmmakers believe their own message deep down. If so, why do they attack the legal system so gleefully, then make such a pallid case against the vigilante ''solution'' they dangle before us? And why is the first half so single-minded about the issues it raises, while the second half - the ''progressive'' half - buries its ideas in a flurry of action scenes?

And is the justice system truly as awful as ''The Star Chamber'' claims? I doubt a mass murderer would go free in California because the arresting officer's uniform wasn't pressed. Yet the cases before judge Michael Douglas are almost that bizarre.

I commend ''The Star Chamber'' for dealing with important issues, and not going crazy in the process like the appalling ''Capricorn One,'' another opus by director Peter Hyams. I'm sorry the film is so clumsy, though, and full of glaring anomalies, like a paid assassin who doesn't know how many shots his two-barreled gun can fire.

And I suspect its sneakily barbaric beginning will carry more weight with viewers than its comparatively humane conclusion, whatever the filmmakers intended. Indeed, a couple of major reviewers have mistaken the picture's message completely, taking the film as a pro-vigilante tract with a ''confused'' conclusion.

At least the cast fares well, given the circumstances. Douglas is dignified beyond his years, and Hal Holbrook is convincing as an older judge who brings him into the ''star chamber'' fold. Yaphet Kotto also deserves special mention, as a dedicated cop.

Hyams moves the action at a fast pace, using lots of old tricks, and making most of them look serviceable, if not fresh. Though he directs with a sledgehammer, not a baton, he knows how to keep us interested even when we've stopped believing what we see. Even the movie's gaffes are in the oldest Hollywood tradition: Note the climax, when Douglas goes through beatings and explosions, yet falls without rumpling his suit or mussing his hair. That's a hero for you. Snow's new trick

Michael Snow's most famous film - and most notorious - is ''Wavelength,'' a 45-minute zoom across a nearly empty room. It's beguiling, complicated in a sly way, and quite fascinating once you get into its slow rhythm. But it's not exactly entertaining, and it certainly won't show up at your nearest multiplex.

Snow always has a new trick up his sleeve, though, and his latest is a doozy. So Is This is the title, and it's as funny as it is rigorous, as engaging as it is inventive.

Try to picture it. The ''characters'' are words, flashed on the screen one at a time. ''This. Is. The. Title. Of. This. Film.'' And so on, like that, for almost an hour.

Sound infuriating? That's what I thought, too, until I found myself chuckling at the very outlandishness of such a movie. Then the words began cooperating with my mood, tossing in jokes and surprises - testing the limits of their own monotony, and looking for variations in their punctilious parade through the projector.

Some of the jokes are mere vulgarities, looking rather out of place amid the growing sophistication of this very clever film. Some of the surprises are ingenious, though, as Snow plays with the shapes, speeds, and rhythms that are his raw materials. The marching words take on lives of their own, inviting us to ponder basic issues of cinema and literature, movies and books, the very acts of watching and reading.

Is this really a film in the accepted sense? I think so. It has a flow of images and a clear sense of development, and that should be enough to qualify as bona fide cinema. It even has visual treats to offer, albeit subtle ones, as bits of stray light play about the edges of the otherwise black-and-white frames.

In any case, it made me laugh and think at the same time, and I'll vote for any strip of celluloid that pulls this off. Look for this elegant opus at museums and other noncommercial showcases - I caught up with it at the New York Public Library - and be ready for a most uncommon treat. Ultimate movie aristocrat

''To be an actor, it is essential to be an egomaniac; otherwise it just doesn't work.''

So wrote David Niven, who passed on recently, in ''Bring on the Empty Horses, '' an amusing memoir of Hollywood high life published nearly 10 years ago. Yet egomania seems to have passed him over during his long and prosperous career, which carried him from extra to Oscar-winner and was still coasting along as recently as a few months ago.

On screen, Niven has always struck me as the ultimate movie aristocrat, as courtly - and removed from the lives of us plebians - as anyone in films. So when I met him a few years ago, I was unprepared for the warmth and friendliness that positively radiated from him.

As the elevator door opened, there he was in stockinged feet, strolling down the hotel corridor to welcome me. He ushered me to his room with an arm draped cordially around my shoulder. Our conversation was a delight, and he followed it up a few weeks later with a chatty, hand-written letter from his Swiss home. The fact that a star of his stature had no need to woo or flatter the press only made his gentlemanly behavior the more striking. As for ego, he remarked that seeing himself on screen made him feel like ''a dog watching a snake'' - just waiting for the wrong or miscalculated move that was sure to come if he just looked long enough.

Niven started his career as a bit player in the 1930s, making a major impression in ''Wuthering Heights'' as early as 1939, but reaching stardom after World War II (in which he actively served) in such still-admired pictures as ''A Matter of Life and Death'' (known to Americans as ''Stairway to Heaven'') and, later, ''The Moon Is Blue.'' Younger audiences remember him mostly for ''Around the World in 80 Days'' in 1956 and ''The Pink Panther'' in 1964, which launched a hugely successful comedy series. He also played in stage and TV productions.

In his later years, Niven turned best-selling author, writing both memoirs and fiction, earning praise for his breezy, conversational style. He was a man for all media - and an outgoing, affectionate person whose off-screen charm complemented one of the most polished on-screen images Hollywood has given us. Film Forum New York

In my July 28 column I praised two excellent Werner Herzog documentaries, ''Huie's Sermon'' and ''God's Angry Man,'' and noted that each deserved to be picked up for widespread distribution.

Now the Film Forum, which gave their American theatrical premieres recently, tells me they are being distributed by New Yorker Films - a smart and forward-looking outfit that specializes in movies for thinking people. I'm delighted these Herzog beauties are in such good hands, and I hope they make their way to theaters everywhere.