Prosecution, defense offer vastly different views of Carolyn Riley

He said defense medical experts had showed that Rebecca died of pneumonia. He added that the child’s psychotropic drugs were not initiated by the mother, but were the result of prescriptions written by Dr. Kayoko Kifuji.

“Carolyn Riley trusted Dr. Kifuji,” Bourbeau said.

He added that the mother did not see Rebecca as a way to receive disability payments. After all, he said, the two older children qualified for benefits, but Rebecca’s application was twice denied.

“Rebecca wasn’t a cash cow,” he said. “She didn’t get any money from disability.”

Jurors are scheduled to return to court Friday to begin deliberations.

The 35-year-old mother faces first-degree murder charges for allegedly overdosing Rebecca with the drugs, and for a “malicious” failure to get her medical attention the day before she died. The judge will give jurors the option of convicting her on a lesser charge of involuntary manslaughter. If convicted of first-degree murder, she faces a mandatory sentence of life in prison without parole; if guilty of involuntary manslaughter, she faces a maximum of 20 years behind bars, prosecutors say.

The verdict may ultimately rest on the jury’s perception of the intentions of Carolyn Riley -- whether she meant to kill her child by giving her a fatal overdose of clonidine, a sedating medication, or whether she is a more benign figure who made some poor choices while being overwhelmed in her troubled life.

Medical testimony has been critical in the case, because prosecutors have attempted to show that Rebecca was over-medicated for many months, culminating with her death by drug intoxication. Defense attorneys say the child died of a rapid-onset pneumonia, not a medication overdose.

The final defense witness was David Benjamin, a Chestnut Hill forensic toxicologist and private consultant who testified that medications played no role in Rebecca Riley’s death.

During his testimony today, Benjamin also displayed at times an incomplete understanding of the case.

For instance, Benjamin testified that vomit had been flowing from the girl’s mouth and nose when she died on Dec. 13, 2006, saying he relied on reports filed by paramedics at the scene.

“There is a mouth full of vomit,” declared Benjamin before jurors.

However, prosecutor Middleton pointed out that medical reports since then, including the autopsy report, showed that the red-pink foamy substance on her face was lung fluid from a pulmonary edema, not the contents of the girl’s stomach, as paramedics and other observers first thought when they saw the child’s body.

When shown a large photograph of the girl’s body, with this pink-red fluid on her face, Benjamin acknowledged that the liquid substance could potentially be fluid from a pulmonary edema.

The finding of such fluid is significant because medical experts for both the prosecution and defense have testified that pulmonary edema is often a sign of drug overdose.

Middleton also interrogated Benjamin about why he confidently relied on test results provided by NMS Labs, a highly-regarded facility in Pennsylvania, for a number of medications in the child's body, but rejected the lab’s measurements of clonidine in the girl’s blood.

“These levels are good, but the clonidine levels are no good?” Middleton asked.

Benjamin later said clonidine redistributes in the body after death in a way that the other medications did not.

Echoing the view of two other defense medical experts, Benjamin also said the lab’s measurement of Rebecca’s clonidine level – at 12 nanograms per milliliter – was based on a blood sample that was obtained in a faulty way, and there is no reliable way of assessing how much clonidine would kill a child.

According to earlier testimony from medical experts for the government and defense, the current established therapeutic range for clonidine is 0.5 to 4.5 nanograms per milliliter. Prosecutors have argued that the girl’s range, therefore, was clearly toxic, and they produced several medical experts who said they believed Rebecca’s clonidine level was deadly.

Defense attorneys have portrayed Carolyn Riley as simply following the advice of her children’s psychiatrist, Kifuji, who had prescribed three powerful psychotropic drugs for each of the three Riley children for bipolar and hyperactivity disorders.

The mother alleges that Kifuji often allowed her to deviate from the prescribed dosages, as needed. However, prosecutors say Riley went far beyond this in her dispensing of drugs to Rebecca the night the girl died.

Patricia Wen can be reached at wen@globe.com