In just three days last week, prosecutors of one of New York's most important murder cases in recent years - the Bensonhurst racial slaying - suffered a series of stunning and embarrassing setbacks.

With little apparent dissent, two separate jury panels determined quickly that three young white men charged with murder and accused of being key players in the death of 16-year-old Yusuf Hawkins were not guilty of the most serious crimes.At the end of murder trials for five of the eight defendants, the district attorney's office in the borough of Brooklyn has won only one murder conviction - that of triggerman Joseph Fama.

Three of the alleged attackers were found guilty of lesser crimes and one defendant was completely exonerated.

Victorious defense lawyers say it's time to question the scenario of the Aug. 23, 1989, slaying presented by prosecutors and the police.

In the early days of the investigation, said defendant James Patino's lawyer, Benjamine Brafman, "there were tremendous pressures on everyone to return indictments quickly to quell the unrest that was upsetting the city. Prosecutors ran with a theory that was not supported by the facts."

Defense lawyers all say Fama acted alone when he shot Hawkins, and the other whites had assembled because they believed outsiders were coming to their insular Bensonhurst neighborhood to cause trouble.

But prosecutors stand by their account of the incident, asserting that Hawkins and his three young, unarmed friends were set upon by a mob of some 30 bat-wielding whites only because they were black.

Fama emerged from the mob, pointed a .32-caliber automatic at Hawkins and squeezed off four shots, two of which tore through his heart.

Hawkins' slaying was the most serious racial incident in the city since the 1986 killing of a young black man by a gang of whites in Howard Beach.

With racial tensions near the breaking point, Hawkins' murder sparked a series of massive, and sometimes violent, demonstrations and protest marches.