NEW YORK -- To the prosecution, the three black men who walked into a Howard Beach pizzeria last Dec. 20 were innocent victims stranded by a broken-down car whose search for help ended in a vicious beating by race-baiting white teen-agers who caused the death of one of the fleeing blacks.

To defense lawyers, the blacks were "the true villains," as one put it, three dangerous men with criminal records, one of whom now admits that he brandished a knife during the incident. And they stress that Michael Griffith, the 23-year-old construction worker killed by a car on the Belt Parkway as he fled from the whites, was a cocaine user and was wanted on an arrest warrant for failing to appear at a hearing in an assault case three weeks earlier.

The Howard Beach murder trial, which opens in a Queens courtroom Tuesday, will likely turn on which portrait proves more convincing to a jury in the racially charged case. The trial, which is being handled by a special state prosecutor, is expected to last about two months.

Two of the white defendants, Jon Lester, 17, and Scott Kern, 18, are charged with second-degree murder in Griffith's death. Michael Pirone, 17, is charged with manslaughter, and Jason Ladone, 16, with attempted murder and assault. Seven others are to be tried separately on rioting and other lesser charges.

A key prosecution witness is expected to be Robert Riley, 18, part of the loose circle of Howard Beach teen-agers, who was also charged with second-degree murder. Riley will be allowed to plead guilty to lesser charges in exchange for his testimony.

It has been 8 1/2 months since the assault heightened tensions in New York and turned Howard Beach, a white, working-class neighborhood in Queens on the edge of Jamaica Bay, into a national symbol of racial intolerance.

Recent pretrial developments appear to have complicated the prosecution's efforts. One of the blacks, Timothy Grimes, 20, who had testified under oath that he had not been carrying a weapon on the night of the attack, changed his story last month, saying that he had pulled out a knife and threatened to use it during the confrontation.

Special prosecutor Charles J. Hynes played down the disclosure, saying that Grimes brandished the knife defensively. In any event, Hynes said in an interview, "All the acts alleged to have occurred happened after Timothy Grimes disappeared and the others went up toward the Belt Parkway."

Hynes also minimized the importance of previous allegations against the three blacks, saying that while this may be used to challenge their credibility, the trial judge, Thomas Demakos, could limit such questioning.

"We just believe the evidence will establish that {the three blacks} were there for a legitimate purpose, and no matter what backgrounds they have, they were the true victims in this incident," said Dennis Hawkins, an aide to Hynes.

But defense lawyers have a different view. "We now have evidence of the fangs of the true villains," said Ronald Rubinstein, Ladone's attorney. "It's an issue of dangerous people coming into a peaceful community. These were men against boys."

"These were three guys with criminal records who displayed knives and got into an antagonistic argument," said Bryan Levinson, Lester's lawyer. "The guy who's dead was using coke. You start to look at the attitude of these guys."

Attorneys for the blacks in the case did not return phone calls.

Griffith was found during the autopsy to have cocaine in his bloodstream.

Grimes, at the time of the Howard Beach attack, was awaiting trial on charges of assault and criminal possession of a silencer, and had been arrested earlier for burglary and criminal trespass. Grimes also faces assault charges in the stabbing of his girlfriend nine days after the Howard Beach incident.

The third black, Cedric Sandiford, 36, whom the Howard Beach teen-agers beat with a baseball bat, has twice been convicted on gun charges. Sandiford also served two years in a Virginia jail for threatening a neighbor with a sawed-off shotgun.

On the other side, Lester, a key white defendant, is currently in Riker's Island prison after pleading guilty to gun possession charges when he was 16.

Lester is alleged to have instigated the attack when, after exchanging insults with the blacks, he returned to a party and said, "There {are} some niggers in the pizza parlor . . . Let's go back and kill them."

Defense lawyers argue that the racial aspect of the case has been overblown and that it was basically a neighborhood turf fight. "This whole case is predicated upon prejudice," Rubinstein said.

Hynes has been consulting with Boston District Attorney Newman Flanagan about his successful prosecution of a similar case. In April 1982, William Atkinson, a black, was killed by an oncoming train after he ran into a Boston train station to elude five taunting, rock-throwing white teen-agers after midnight.

The whites were convicted, two on manslaughter charges, under what Flanagan calls the "tunnel theory." With the tracks enclosed by barbed-wire fences, he said, Atkinson "had no other option" but to flee from the station "where the white guys were waiting."

Hynes noted that while the Boston victim was struck by the train more than a quarter-mile from where the chase stopped, the distance between Griffith and his pursuers when he jumped a divider and was killed on the Belt Parkway was "less than 175 feet."

But there is disputed testimony about the defendants' whereabouts when Griffith was struck. "The prosecutor is drawing lines," said Gabriel Leone, Kern's lawyer. "If you're this close to the highway, you're guilty of murder; if you're this close, you're guilty of manslaughter. I don't buy that."

Both the defense lawyers and Hynes, who took over the case after key witnesses refused to cooperate with the Queens district attorney, agreed that picking an unbiased jury will be time-consuming. Hynes said that New York's three major daily newspapers published nearly as many stories about the case in a six-month period as they did about subway gunman Bernhard H. Goetz over 2 1/2 years.