Court of Appeals of Mississippi Reverses Murder Conviction Based on Forensic Pathologist Relying on Investigator’s Allegations

February 27, 2025

Mississippi Rule of Evidence 702 provides that

A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:

(a) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;

(b) the testimony is based on sufficient facts or data;

(d) the expert has reliably applied the principles and methods to the facts of the case.

So, is it error under Rule 702 for the court to allow a forensic pathologist to testify that the victim’s cause of death was a “homicide” based on what he was told by investigators in a case? According to the recent opinion of the Court of Appeals of Mississippi in Roncali v. State, 2025 WL 560297 (Miss. App. 2025), the answer is “yes.”

In Roncali, Carlos Roncali was convicted of capital murder for the death of his wife, Marian Chaney Roncali.

At trial, Dr. Mark LeVaughn testified for the State as an expert in the field of forensic science. Before and during Dr. LeVaughn’s testimony, Roncali objected to the trial court for allowing Dr. LeVaughn to testify that in his opinion, the manner of death was homicide. On appeal, Roncali…contend[ed] that the trial court erred by allowing this testimony.

As the Court of Appeals of Mississippi noted,

In a hearing outside the presence of the jury on Roncali’s objection to Dr. LeVaughn’s testimony concerning the manner of death, Dr. LeVaughn testified that when speaking with investigators in this case, he was “informed that the methamphetamine was administered to her,” and he said that he relied upon that information in forming his opinion. He further testified that when “homicide” was used to describe the manner of death in forensic cases, it meant that the “person’s death results from the actions of another.” At the conclusion of the hearing, the defense argued Dr. LeVaughn’s opinion that the death was “caused by someone else’s actions [was] a leap that needs to be based on more than what has been said so far.” The trial judge ruled as follows:

Apparently, there’s no way to tell – I don’t know how this methamphetamine was placed into the body of the victim. I don’t know if it was taken orally, injected or some other way. There’s been no testimony about that, and apparently Dr. LeVaughn wasn’t able to tell because he hadn’t testified to it. But it had to get inside of her somehow, and that’s where the outside information comes relevant to whatever opinion that he’s going to reach. So my opinion is that he’s perfectly entitled to form his opinion based on everything that he knows about this case, whether it’s from his own personal observation or information that he gained from other sources. So your objection is overruled.

On appeal, the Court of Appeals of Mississippi reversed this ruling and granted a new trial, concluding

We find that the trial court abused its discretion by allowing Dr. LeVaughn to testify that the manner of death was homicide, in that the death resulted from the acts of a third person injecting methamphetamine into the victim. The trial court, as a part of its gatekeeping role, must consider the reliability of the foundational facts upon which an expert bases an opinion. The sufficiency of this information is a question of law. The statement by an unidentified investigator was “unsupported speculation or subjective belief” and was not a “reasonably accurate basis” to support Dr. LeVaughn’s expressed expert opinion that the manner of death was homicide.

-CM