Elizabeth Holmes Conviction Stands Despite “Harmless Error”
Elizabeth Holmes was the founder of Theranos a company that claimed to be able to test blood with a pin prick.
Harmless Error and the Speculative Nature of Expert Witness Testimony in Criminal Trials
I’ve been connected to this case since its inception. One of my early Fox News appearances was with David Asman on Neil Cavuto’s show related to Elizabeth Holmes. I dove into the research and learned the case. Let’s just say, there were some problems. Big problems.
The Ninth Circuit’s recent opinion affirming Elizabeth Holmes and Ramesh "Sunny" Balwani’s convictions in the Theranos fraud case brings us a troubling trend in criminal trials: the reliance on "harmless error" to dismiss challenges to problematic expert testimony. In particular, the testimony of Dr. Kingshuk Das, Theranos’s former lab director, illustrates how courts allow speculative conclusions from expert witnesses to stand, even when those conclusions were not subject to proper evidentiary scrutiny under Daubert v. Merrell Dow Pharmaceuticals, Inc. (509 U.S. 579, 1993).
In recent years, Courts have leaned too heavily on the harmless error doctrine when dealing with expert witness testimony, particularly in cases where the expert’s conclusions bear directly on the core issues of fraud or scientific validity.
The Ninth Circuit’s decision, which acknowledges errors in the admission of expert-like testimony yet deems them harmless - a brutal mis-application of the “harmless error” standard.
Expert Witnesses in Criminal Trials: A Matter of Scientific and Legal Integrity
Expert witnesses hold a special status in criminal trials. Unlike lay witnesses, who may only testify to facts they personally observed, expert witnesses are permitted to offer opinions based on their specialized knowledge, training, and experience. This privilege, however, comes with an important caveat: expert opinions must meet the reliability standards set by Federal Rule of Evidence 702 and be vetted through the Daubert standard. These requirements exist for good reason—scientific testimony carries a unique weight with juries, making it imperative that such testimony is rigorously scrutinized.
In the Holmes and Balwani case, Dr. Das, a former Theranos lab director, was allowed to testify that Theranos’s Edison blood-testing device was "unsuitable for clinical use" based on retrospective data analysis he conducted after the company was already collapsing. The Ninth Circuit acknowledged that Das’s testimony, particularly his conclusions drawn from the Patient Impact Assessments (PIAs), constituted expert opinion that should have been subject to Daubert review. Yet, the court ultimately ruled that the improper admission of this testimony was harmless error.
This raises an unsettling question: how can it be harmless to admit testimony that is both technical in nature and directly tied to the core allegations of fraud? If the reliability of Theranos’s technology was at the heart of the case, then the expert witness assessing that technology should have been scrutinized accordingly. Instead, the court bypassed this requirement by asserting that even if the testimony had been admitted improperly, the sheer weight of other evidence made the error irrelevant.
This is an incredibly dangerous precedent.
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The "Harmless Error" Problem in Expert Testimony
The harmless error doctrine is meant to ensure that minor procedural missteps do not derail an otherwise valid conviction. However, courts have increasingly used it as a shield to excuse substantive errors—especially in cases involving scientific or expert testimony. When judges declare an error "harmless," they are essentially engaging in speculation about what influenced the jury, a practice that is fundamentally at odds with due process.
Consider the implications of this approach in the Holmes case:
The government introduced expert testimony without vetting its reliability under the proper Daubert standard.
The jury was exposed to scientific conclusions that were never properly challenged for validity.
The court acknowledged the expert testimony was improperly admitted but dismissed concerns by speculating that the jury would have reached the same verdict anyway.
This is particularly problematic because the reliability of scientific evidence is often opaque to jurors. Jurors are likely to trust scientific testimony as definitive, making it imperative that courts ensure that such testimony is properly vetted before it reaches the jury.
By contrast, courts rarely treat defense evidence with such generosity. If a defense expert were admitted without Daubertscrutiny, the prosecution would rightly object—and most courts would agree that the improper admission required a retrial rather than a mere harmless error finding.
A Speculative Foundation: The Danger of Allowing Courts to "Guess" at Jury Impact
At its core, the harmless error doctrine is speculative when applied to expert testimony. It requires appellate courts to guess at what influenced the jury’s decision-making. This is particularly problematic in fraud cases, where credibility and technical evidence often play a decisive role. If the jury had been presented with a properly challenged expert, perhaps the defense could have undermined the reliability of the conclusions, weakening the prosecution’s case. We’ll never know, because that process never occurred.
Imagine a case where a forensic scientist claims a defendant’s DNA was found at a crime scene, but later it turns out that:
The scientist did not follow proper testing protocols.
The methodology used was not vetted under Daubert.
The scientist’s conclusions were admitted as evidence anyway.
The court then says, "Well, there was a lot of other evidence, so this was harmless."
The problem is obvious: it is impossible to separate the improperly admitted scientific testimony from the jury’s decision-making process. The same applies to expert testimony in fraud cases—once the jury hears an expert claim that a technology was "unsuitable for clinical use," that statement has already framed the case, whether it was properly vetted or not.
The Need for a Higher Standard of Review in Expert Testimony Cases
The Ninth Circuit’s handling of the expert witness issue in the Holmes and Balwani case is emblematic of a broader failure in the criminal justice system. The harmless error doctrine is too often applied speculatively in cases involving expert testimony, allowing courts to excuse improperly admitted scientific opinions simply because they believe—without definitive proof—that it did not impact the jury’s decision.
This practice must change.
Daubert Review Must Be Mandatory – Any expert opinion used in a criminal trial must be vetted under Daubert, and failure to do so should constitute reversible error, not mere harmless error.
Burden on the Government – If expert testimony is improperly admitted, the government should bear the burden of proving that it did not affect the jury’s decision—rather than courts simply assuming it didn’t matter.
Higher Appellate Scrutiny – In cases involving scientific testimony, courts should be required to assess the record rigorously before concluding an error was harmless, instead of engaging in speculative reasoning about jury impact.
At the heart of criminal justice is the requirement that convictions be based on reliable evidence. Expert testimony—particularly when dealing with scientific or technical subjects—should not be excused from proper scrutiny simply because a court deems the conviction likely valid regardless.
If anything, scientific testimony requires the highest degree of scrutiny, not the lowest. And until courts stop speculating about the impact of improper expert testimony, we risk allowing junk science, unreliable conclusions, and prosecutorial overreach to define the outcomes of criminal trials.
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