The woman charged with murdering her 6-year-old son and leaving him bound in a bathtub last month in Southeast Washington is competent to stand trial, a D.C. Superior Court judge ruled yesterday.

But the finding, made after the judge reviewed a report from a government psychologist, does not mean that the mental health of Julia Barber is no longer an issue in the criminal case against her. An insanity defense is still a possibility, but Barber's lawyers do not have to make such a claim for some time, perhaps months, giving them time to study Barber and their options.

Barber, 27, is charged with killing Donmiguel Nathaniel Wilson Jr. on July 18 by beating, suffocating and drowning him in the family's apartment on Wheeler Road SE.

Barber, who was arrested and charged Saturday, has been at St. Elizabeths Hospital since the day after her son's death. She was taken to the psychiatric hospital after her behavior turned erratic during questioning, police said.

In her report to the court, psychologist Elizabeth Teegarden outlined what she had learned about Barber from interviewing her and from hospital records.

Barber first received mental health treatment when she was 15 but did not follow up on her care, Teegarden said. Barber said she had "overdosed" on pills -- "so many that I can't remember" -- and after being taken to an emergency room spent 21/2 months at a Montgomery County psychiatric center, according to the report.

But when she was sent home, Barber did not continue her therapy.

"I didn't want to go. . . . I never liked counseling," she said. "I didn't think it was necessary for a suicide attempt." Instead, she coped with sadness, as she always had, according to the report, by "blocking sad things out."

Her stay at the Montgomery facility was the last time she received mental health care until after her son was dead and she was suspected of killing him, she told the psychologist.

At yesterday's hearing, Barber, a petite woman with short hair, was shackled at the ankles and wrists. She was calm and quiet as she stood next to her attorney. She had been taking an antipsychotic drug and an antidepressant, she told Teegarden.

The competency ruling means that the judge has found that Barber will be able to understand and participate in the trial. Her lead attorney, Santha Sonenberg, agreed that Barber is competent but suggested that the state of her mind is fluid. "None of us can portend the future," Sonenberg said.

Barber told the psychologist that she continued to hear voices and that when she was recently moved, the voices became more intense. "They wanted me to end all the pain and suffering I've caused," the report quoted her as saying. "They were telling me to end it all."

The psychologist concluded that Barber must "remain on psychotropic medication in order for her to maintain competency." Under the law, a judge must consider a number of factors in deciding whether a defendant may be medicated for the purpose of making the person competent to stand trial.

Barber's attorneys could challenge the admissibility of any incriminating statements made during police questioning. At one point, Barber indicated to police that she wanted to leave, but the questioning continued, law enforcement officials have said. Prosecutors raised questions about the tactic, and it was only after weeks of additional investigation that an arrest warrant for Barber was issued. On Monday, Sonenberg told a judge that the statements cited by prosecutors were "dubious."

But the insanity issue is the one most likely to loom over the case.

If her attorneys believe that Barber could not recognize right from wrong because of a mental disease at the time of the killing, she could plead not guilty by reason of insanity. The hospital's experts would then offer their opinions, as would experts hired by the prosecutor. If the experts agreed with the defense, the case could be resolved with a judicial determination that Barber was not guilty by reason of insanity.

But if the prosecutors did not agree with the findings of other experts, the case probably would proceed to trial, where insanity pleas are hard to defend.

A psychologist's report details the mental health history of Julia Barber.