The details keep piling up in the case of University of the District of Columbia President Robert L. Green, and none of them is helpful to his cause. A story in this newspaper Wednesday described a new series of hotel, car rental and room service bills run up by Dr. Green and Cassandra A. Simmons, a former student of his at Michigan State University who is now on the faculty there and who helped him with his just-published book on school desegregation. The bills were all paid by UDC. On one occasion, as Dr. Green was taking over as UDC president in October 1983, Miss Simmons came here; she was serving as a consultant. In that same month she went to Boston for "a higher-education conference," which Dr. Green appears to have attended as well. In May of last yar they returned to Boston for a three-day weekend. According to UDC spokesman Gilbert Maddox, this was to work on the book, the royalties from which Dr. Green has said he is donating to UDC. "She was a major force in the final publishing of his book," Mr. Maddox said.

The records on which the story was based also run to flowers. One of Dr. Green's sons spent $42.50 of UDC funds to send a dozen roses to a woman on the university staff. There were flowers for Mayor Barry on his birthday last year, for former deputy mayor Ivanhoe Donaldson on his birthday the year before -- and last year for Mrs. Green on Mother's Day. Dr. Green has agreed to repay the university for some flowers the D.C. auditor found he had impermissibly charged to his university account; these are presumably among them. But that is not the point. The point is Dr. Green's sense of the standards of public office. He is paid $74,900 a year. He is given a house, two housekeepers, a car with telephone and chauffeur, and life, health and disability insurance. The uni- versity makes payments in his behalf into a re- tirement fund. He can afford to buy his own flowers. His record in office has a buccaneering quality to it.

Ronald Brown, chairman of the UDC board of trustees, said in these pages Sunday that the board is well aware it has a decision to make in the case of Dr. Green. Increasingly events seem to be making the decision for it. If Dr. Green has a more convincing defense to make than he has made so far, he should make it soon. We say again: UDC is among the most important, yet most fragile, institutions in this city. It is not a piggy bank. It deserves the best possible leadership. That is not what it has recently had.