ALEXANDRIA, Va. – Two relatives of victims of the September 11, 2001, attacks testified for the defense yesterday in Zacarias Moussaoui’s death penalty sentencing trial. One told the jury her family does not want to “get caught in a whirlpool of sadness and anger.”

A medical sociologist, Marilynn Rosenthal, whose son Josh was killed at the World Trade Center, said her family feels strongly “something good has to come out of what happened” and family members have endowed an annual lecture on the attacks of September 11, 2001 at the University of Michigan, where she teaches.

Robin Theurkauf, whose husband, Tom, died in the South Tower, also testified that “the Bible attempts to explain that we are all sinners, all broken people, but all children of God and loved by God.”

Several members of the jury, which heard heart-rending tales during the prosecution case from almost four dozen victims and their relatives, leaned forward when they realized relatives were there to testify on behalf of the team trying to save the 37-year-old Frenchman from execution.

Earlier a second defense expert to diagnose Moussaoui as a paranoid schizophrenic testified that mental illness probably afflicted Moussaoui throughout his time as an Al Qaeda operative.

A psychiatrist, Michael First, who edits the diagnostic manual used by the psychiatric profession, described for jurors how Moussaoui’s mental illness apparently affected his ability to function within Al Qaeda and his ability to prepare a defense for his death penalty trial.

Mr. First said Moussaoui’s schizophrenia manifests through paranoid delusions and through disorganized thought and speech.

He said this is consistent with earlier trial testimony that Al Qaeda leaders considered Moussaoui paranoid and even “cuckoo,” and was unable to follow basic orders, like minimizing phone contact with others in Al Qaeda. A planner of the September 11, 2001, attacks, Khalid Shaikh Mohammed, said in a written summary given to jurors that he wanted to dismiss Moussaoui from the planned hijacking operations altogether.

The illness has also affected Moussaoui’s ability to defend himself at trial. Specifically, his delusion, fueled by a dream, that President Bush will free him from prison, has left him indifferent to what the jury thinks of him.

“It has allowed him to act in a way that is self-defeating and harmful,” Dr. First said, referencing the two times Moussaoui has taken the stand in self defense and done his case more harm than good.

Mr. First is the second defense expert to conclude Moussaoui is a schizophrenic, but Mr. First was able to more clearly relate Moussaoui’s illness to his often bizarre and self-defeating actions.

Also yesterday, an expert on cults testified that Moussaoui’s isolation from family and social support networks left him vulnerable to recruitment by the terrorist network.

A psychologist, Paul Martin, a former cult member who now runs a treatment center for cult victims in Albany, Ohio, said French Moroccans such as Moussaoui generally feel alienated from Western society and his state of mind suffered even more when he left France in 1992 to study international business in London.

“He’s away from his family. He’s lonely. He’s complained about racism. He’s in a new country, and he doesn’t have any support group,” Mr. Martin said, describing Moussaoui’s embrace of radical Islam in the mid-1990s.

On cross examination, Mr. Martin acknowledged studies exist that find most Al Qaeda terrorists come from stable families, middle-class backgrounds and have a college education.

Mr. Martin’s testimony was allowed by U.S. District Judge Leonie Brinkema, but at the insistence of prosecutors, the judge barred any suggestion from Mr. Martin or others that Moussaoui had been brainwashed by Al Qaeda.

While not specific to Moussaoui, defense lawyers introduced information from a 2003 CIA report that stated Al Qaeda training camps in Afghanistan “used brainwashing techniques to cement loyalty” among recruits.

Moussaoui said as he was led out of the courtroom at a recess, “Moussaoui fly over the cuckoo’s nest,” the latest Hollywood-inspired interjection mocking those who question his sanity.

Much of the mental-health testimony has revolved around Moussaoui’s belief Mr. Bush will set him free. Prosecutors and defense lawyers differ on whether that belief is a schizophrenic delusion or a fundamentalist Muslim’s article of faith.

Moussaoui’s defense team contends his belief about Mr. Bush shows he has lost touch with reality. They hope evidence that Moussaoui suffers from mental illness will persuade a jury to spare his life.

Moussaoui is the only person charged in this country in the September 11, 2001, attacks. The jury deciding his fate has already declared him eligible for the death penalty by determining that his actions caused at least one death that day.