The investigation into the case of a black teen-ager who claims she was sexually assaulted by six white men has again reached an impasse with lawyers for the victim saying they will not cooperate with prosecutors. Representatives of the victim met with state Attorney General Robert Abrams, the special prosecutor investigating the case, for 12 hours Tuesday and Wednesday but failed to secure a pledge from Abrams that he would personally handle several key aspects of the case. Without that, ``we are unable to give him the cooperation that he is demanding of us,'' Alton Maddox Jr., an attorney representing Tawana Brawley and her family, said at a news conference after Wednesday's meeting. ``There is no way that we can agree that we have, instead of a special prosecutor, a case manager,'' he said. ``We are looking for a special prosecutor to personalize this case.'' Abrams said in a statement that he was committed to personal participation in, as well as overall responsibility, for the case. But he said it was too early to make the specific tactical decisions demanded by Maddox, attorney C. Vernon Mason, and activist Al Sharpton. Abrams said the investigation will continue without the cooperation of Miss Brawley or her attorneys. The two sides have no immediate plans to meet again, said Abrams' spokesman, Timothy Gilles. Miss Brawley, 16, of Wappinger Falls, claims she was repeatedly raped and assaulted last November by six white men, one of whom flashed a police badge. She was found four days after her disappearance in a daze, wrapped in a plastic bag. Racial epithets had been scrawled on her body. This week's talks followed a meeting Feb. 11 between Miss Brawley's representatives and Gov. Mario Cuomo, which appeared to break a stalemate that had stymied the investigation. Previously the representatives had refused to allow Miss Brawley or her family to cooperate in the probe, saying they didn't think John Ryan, the aide Abrams had picked to head the investigation, had sufficient experience in civil rights matters. The attorneys later said they had been assured by Cuomo that Abrams would be ``personally involved'' in the investigation. In the meetings this week the representatives made Miss Brawley's cooperation conditional on Abrams personally conducting certain aspects of the case, including grand jury presentation and direct examination of several witnesses, Abrams said. ``I have indicated that I do not rule out performing any or even all of these roles myself,'' said Abrams. ``However, we are far from any trial here, we are far from even solving this case, and these are questions of trial tactics that I and my staff of prosecutors feel cannot in good conscience be made at this time.''