WHETHER THEY'RE trying to evoke empathy or provoke reaction, the five artists now showing at the Washington Project for the Arts have an unfortunate tendency to let the medium mask the message.

Miso Suchy and Lida Suchy spent four years documenting the Gypsies of eastern Slovakia. The result is a melange of photographs and a herky-jerky film of oddly appealing people living in dreadful squalor.

The half-hour film was named best documentary at a 1988 Czechoslovakian film festival, but then the judges presumably knew something about the Gypsies, and also could understand what they were saying. As presented here, the English voice-over and subtitles are unsatisfying, leaving us to flounder: Is that young man on trial? Did he kill the little girl lying on the bier? The photographs are left uncaptioned, which is unfortunate because only a few speak for themselves.

Steve Daiber draws and paints on illustrations torn from ancient tomes of science and medicine. He calls them palimpsests, although the original images are not erased, and says his drawings are intuitive reactions to technology and reflect his dismay at the environmental destruction of the past century. The viewer's reaction may be dismay at the destruction of the books.

Renee Stout presents a "spirit house" filled with everything from home-canned tomatoes to human bones, all selected for their positive and healing force. There are hundreds if not thousands of "spiritual power objects" in the murky interior of the walk-in cabin, and the effect is kooky-spooky, not hallowing so much as Halloweenish.

Fred Wilson either was born yesterday or needs to get out more. His creation, which shows more promise and less fulfillment than any of the others, is a satirical "museum" displaying the insensitivity and outright racism of early Eurocentric anthropologists and ethnologists. But the soul of satire is wit, and Wilson's style runs to ranting.

Also, his misunderstanding of his own materials undermines Wilson's message. Attempting to equate American Indians with endangered species, Wilson brackets them with the wild turkey and osprey, whose booming populations are conspicuous examples of successful conservation.

He holds up a white anthropologist's straightforward nude photographs of a South American Indian woman as an example of insensitivity, as though it were possible to record human physiques through clothing. Then, demonstrating that apples don't grow on orange trees, Wilson contrasts this scientific documentation with photographs taken by an indigenous commercial photographer of Indian women wearing their (Western-style) finery. Somewhere in there the point of his message gets blunted.

Which is a shame, because some of Wilson's jabs are sharp, as in the vitrine of a skeleton labeled "The Last Ancestor From the Last Excavation of the Last Sacred Burial Site," and a television monitor showing a Hollywood Zulu Wars movie that must be viewed through the eyeholes of an African ceremonial mask. But the points Wilson scores against white ethnocentrism get wiped out by such self-destructing pieces as a bust of "The Last Murdered Black Youth." Just about everybody but Fred Wilson must be aware that the principal murderers of black youths are . . . black youths.