Federal Court Judge Frank A. Kaufman, listening to testimony on the first day of the reopened Prince George's school desegregation suit, defended aspects of the schools' 1973 busing plan and challenged a key NAACP witness to show how the plan could have been made to work better.

Early in the day-long session, Kaufman said he had "little doubt" that parts of the original 1973 desegregation plan had not been followed but left open the question of who was to blame.

But as William Lamson, an expert witness in analyzing school segregation patterns, cited examples of how racial concentrations increased at several schools, Kaufman repeatedly stopped him to ask if the size of the county and transportation problems in busing students had been considered.

Kaufman, who oversaw the design of the original plan, said that nothing in his 1972 order or the plan intended for students to move "back and forth from far-flung areas of the county."

NAACP lawyers have argued that there are almost as many "racially identifiable" schools this year as there were in 1972.

But because of the size of the county and its residency patterns, Kaufman questioned whether it is proper--as the NAACP argued--to apply a county-wide standard to identify a school as "black" or "white".

"This testimony keyed into county-wide averages does not take into account that you cannot transfer people around on a county-wide basis, only a sector basis," Kaufman said.

School officials would not comment directly on the opening events in what is expected to be a four-week trial. But, as Kaufman repeatedly stressed the problems of designing the original busing plan, school Superintendent Edward J. Feeney could be seen smiling and nodding his head in agreement.

Feeney, who worked directly with Kaufman on the plan in 1972 when he was assistant superintendent, said he was confident that the school system will be vindicated.

Lamson, who has testified on behalf of the NAACP in some 30 school desegregation cases over the last 12 years, responded to tough questioning by Kaufman by conceding that he had not taken transportation patterns or the demographic changes in the neighborhoods into account.

"If the transportation patterns have not been studied, then the testimony is not very helpful to the court," Kaufman said. "Many, many days, not just ours, were spent trying to analyze these problems," he added.

With the judge repeatedly shaking his head or thumping his armchair in frustration over Lamson's inability to address certain questions, NAACP lawyer Joseph Hassett cut short Lamsom's testimony. Hassett said Lamson's opening remarks were only for the purpose of giving examples from the massive statistics that support the NAACP case.

Thomas Adkins, national NAACP chief legal counsel, said that any problems with the Lamson testimony would be straightened out as the trial progresses.

"I have been through close to 20 of these cases and they all raise the same question at the outset; given the tremendous amount of data, how do you present it in the most concise manner?" Atkins said. "It is not unusual for the court to force both sides to be as precise as possible in their positions," he added.