"Fighting Back" is a lurid glorification of urban vigilantism remotely inspired by the career of Anthony Imperiale, the charismatic community leader of riled and fearful Italian-American residents in Newark in the late '60s. Imperiale himself is recalled in newsreel clips in the course of the movie, which opens for no justifiable reason with a medley of traumatic documentary footage, from the assassination of President Kennedy through the assassination attempts on President Reagan and Pope John Paul II.

The protagonist is an indignant raging bull called John D'Angelo, the owner of an Italian-American deli and catering service in Philadelphia. When his pregnant wife and elderly mother are severely injured by local riffraff, D'Angelo organizes a volunteer protective service, the People's Neighborhood Patrol, and proceeds to ride roughshod over pimps, pushers and muggers. While there are murmurs of skepticism and disapproval from certain representatives of the police and the city government, the opposition seems to have been mysteriously disarmed by D'Angelo's shock tactics. With everyone from the police commissioner to the local godfather guaranteeing tacit approval, D'Angelo climaxes his campaign by firebombing three bad hombres, a terroristic beau geste that supposedly restores peace and security to his home town.

There are fleeting indications that the filmmakers--director Lewis Teague, who did a creditable job with John Sayles' witty "Alligator" last year, and screenwriters Tom Hedley and David Z. Goodman--recognize traces of demagoguery, racism and willful ignorance in their protagonist, who's occasionally taken to task for flying dangerously off the handle.

Dynamic leading roles are no doubt a temptation for any actor, but Tom Skerritt would have been wiser to resist the forceful indignity of D'Angelo. It's a De Niro-reject sort of role that doesn't suit Skerritt's reserved, watchful personality, a reliable source of calm, rational strength in four earlier movies--"M*A*S*H," "Fuzz," "The Turning Point" and "Alien." He looks acutely miscast as a wrathful brawler and compares most unfavorably as a potential leader of men with the corpulent but commanding Imperiale, who imposes more authority in about 20 seconds of old clips than Skerritt can generate with an entire runaway vehicle at his disposal.

In fact, a good deal of acting talent is wasted on negligible or disreputable material in "Fighting Back." Patti LuPone, the original "Evita," gets her first substantial movie role as D'Angelo's wife, and there's something compelling about her oversized features and aura of discontent. Still, the interesting hints of marital tension that she suggests are strictly gratuitous shades of characterization.

Michael Sarrazin, whose career took an unfortunate detour at least a decade ago, has been improbably cast as D'Angelo's best friend, an Italian-American cop, but he emerges as a more attractive figure by embodying the self-control and sense of social responsibility that the hero lacks. One of Skerritt's crewmates from "Alien," Yaphet Kotto, heads a formidable auxiliary of black actors in superficial supporting roles. Kotto turns up as a community organizer called Ivanhoe Washington, a character about as loosely related to Leroi Jones as John D'Angelo is related to Anthony Imperiale. Ted Ross of "The Wiz" and "Arthur" makes a light snack of the smoothly corrupt police commissioner, while Jim Moody, who gave "Fame" a glimmer of educational reality as the drama teacher, confirms the good impression as a black businessman aligned with the predominantly white People's Neighborhood Patrol.

All of them are impressively overqualified for the minimal, motley quality of illusion that "Fighting Back" is content to confuse with effective contemporary melodrama.