Robert D. was 12 years old, good-looking, cooperative and quiet, the psychiatrist recalled, but he seemed unable to look the doctor in the eye and his hands trembled slightly. Probing gently, the doctor said he knew all children were afraid of some things. What was Robert afraid of?

"People," the boy replied. The psychiatrist was stunned. Why, he asked. "Because people threaten people," the boy said. "They have guns. They die in front of your face."

In all his years of evaluating children who are veterans of the District's child welfare system, Richard L. Gross testified yesterday in federal court, "I have never heard a child say they were afraid of people." Robert's blunt answer, Gross said, was "the plaintive expression of a child who is not trusting of people as a child ought to be."

Gross's testimony came on the second day of trial in a class-action lawsuit charging that the District's child welfare system has abused the rights of the roughly 2,200 children in its care by warehousing them in foster homes instead of putting them up for adoption. The lawsuit, filed by the Children's Rights Project of the American Civil Liberties Union, seeks reform by putting the D.C. Child and Family Services Division under court supervision.

Robert D.'s story was one of three case histories detailed yesterday for U.S. District Judge Thomas F. Hogan, in an effort by ACLU lawyers to depict the long-term harm done to children who spend years in foster care.

"Everything we know says young children need a family, particularly a child with serious problems," testified Clarice Walker, an associate professor at Howard University's school of social work.

But children in foster care often don't get that "nurturing parent," according to testimony by Walker and Gross, who heads the Fairbridge Residential Treatment Center in Rockville. Also testifying were Gordon Kirschner, a psychiatrist at the Washington School of Psychiatry, and Harold Eist, of Bethesda, a psychiatrist also on the Howard faculty.

All four had interviewed children, ranging in age from 6 to 12, who are among the lawsuit's plaintiffs and reviewed the records on their care. All the children are veterans of numerous foster homes, the doctors testified, and all show similar psychological problems: depression, hyperactivity and learning disabilities.

All four predicted a bleak future for the children: troubled relationships, recurring depression and problems in school that eventually would translate into problems getting and holding jobs.

Robert D. was one such child. According to documents in the case, the District took custody of him when he was 7, after his mother left him and his siblings alone in their apartment for three days. Records show she also admitted beating him. Robert's new foster mother also beat him.

By the time Gross talked to Robert D. last summer, the boy had been in five foster homes and one group home. His dislike of people was so intense that he refused to draw a person for the doctor and played only with the animal puppets in Gross's office.

Kirschner's evaluation of Leo C. was similar. Leo was put in foster care when he was 2 months old, after his mother was hospitalized for depression. Court records show that over the years his mother had left him and his brother on the city's doorstep several times. By the time he was 6, Leo's longest stay at any foster home was 18 months, Kirschner said, and that foster mother had disappeared last summer while Leo was at camp.

Kirschner said that when he talked to Leo soon after that, the 8-year-old was living with his stepbrother's grandmother, whom he called "Mommy." He seemed strikingly nonchalant about his foster mother's disappearance, leading Kirschner to conclude that his attachments to people were shallow and easily transferred -- his only defense against abandonment.

LaShawn A. was brought to the Child and Family Services Division when she was nearly 2 by her mother, who was homeless. A social worker's description of the child: "Underweight and anemic, did not speak and appeared sad."

Eist testified that by the time he saw LaShawn last year, the 6-year-old showed evidence of hyperactivity as well as the depression the social worker had noted five years earlier.

He predicted more episodes of depression in her adult life, the inevitable result of a childhood with no consistent nuturing. It was a cycle, he said, of "torment, abuse, pain and mortification" from which the little girl likely was never to recover fully.