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Elizabeth Holmes- Case Archive
personpersonJames MattisJames MattisRetired U.S. Marine Corps general, former U.S. defense secretary, and former Theranos board member.← All People
WitnessTheranos

James Mattis

Retired U.S. Marine Corps general, former U.S. defense secretary, and former Theranos board member.

AppearedFederal Criminal Trial
698 lines·20 proceedings·17 mentions

About

James Mattis testified for the prosecution about his initial interest in Theranos while commanding U.S. Central Command. Holmes's description of a small device capable of rapidly performing many blood tests from a fingerstick led him to propose a regulated, side-by-side military experiment. He said the experiment was not completed during his command and that he knew of no military deployment or treatment use.

After retiring, Mattis joined Theranos's board and invested approximately $85,000. He testified that Holmes was initially his principal source of information and that board materials reinforced his understanding that Theranos's own analyzer provided broad, rapid, accurate testing supported by outside validation. He did not recall being told that most tests relied on third-party equipment or that the Theranos analyzer could perform only a small number of tests.

Defense counsel established that Mattis lacked scientific, engineering, and clinical-laboratory expertise and could not independently validate the technology. Cross-examination also addressed his board compensation and stock options, restrictions on information related to military activity, and his assumptions about test capacity, commercialization, and regulatory approval. Mattis distinguished his assumptions from matters he could independently assess and qualified his recollection of several documents, meetings, and dates.

On redirect, Mattis said that disclosure of the analyzer's limited role in Theranos testing would have prompted board questions. Although he continued supporting the company after the 2015 reporting, he testified that repeated surprises and insufficient transparency eventually left him unsure what to believe, approximately by mid-2016.

Trial Record (20)

FederalFederal Criminal TrialAug 31, 2021 – Jan 3, 2022Called by prosecution

James Mattis testified about the uncompleted military experiment he proposed, his later Theranos board service and investment, and his reliance on claims about the company's testing technology. Cross-examination examined his lack of technical expertise, compensation, assumptions, and qualified recollection, while redirect addressed disclosures that would have prompted board questions and his eventual uncertainty about the company.

Day 10

DirectJames Mattis — DirectJames MattisJohn C. Bostic9highlights361lines spoken

Summary

James Mattis described how Holmes's claims about a small, broadly capable analyzer led him to support a military pilot, join the Theranos board, and invest, before disclosures about third-party equipment and unresolved accuracy questions eroded his confidence.

Highlights (9)

testimony highlightMattis explained that he advocated only a side-by-side military pilot, not diagnostic use, because the technology needed to prove its accuracy, speed, and reliability before treating casualties.Open in transcript →
Quote“YOU DON'T TAKE CHANCES ON SOMETHING LIKE THAT. IT NEEDS TO PROVE ITSELF BEFORE IT'S BROUGHT IN, AND THERE'S A CERTIFICATION PROCESS IT HAS TO GO THROUGH, BUT I WANTED TO GET IT STARTED.”— James MattisMattis described proof and certification as prerequisites for military medical use despite his initial enthusiasm.Open in transcript →
admissionMattis testified that he joined the Theranos board, invested approximately $85,000, and relied on Holmes as his sole source of information about the company and its technology at that time.Open in transcript →
testimony highlightUsing the 2013 board presentation, the government elicited Mattis's understanding that Theranos's own analyzers could run a broad test menu and his testimony that disclosure of a 12-test limitation or substantial third-party analyzer use would have mattered to him.Open in transcript →
Show all 9 highlights
confrontationMattis described how the 2015 Wall Street Journal article and board emails revealed that Theranos used venous draws and third-party equipment more extensively than he had understood, creating what he viewed as reputation, integrity, and transparency concerns.Open in transcript →
testimony highlightMattis agreed that independent blind accuracy testing was urgently needed, said it was not completed to his knowledge during his tenure, and testified that he eventually did not know what to believe about Theranos.Open in transcript →
Quote“YES. I DON'T RECALL THE EXACT TIME. THERE JUST CAME A POINT WHEN I DIDN'T KNOW WHAT TO BELIEVE ABOUT THERANOS ANYMORE.”— James MattisMattis summarized the eventual collapse of his confidence while preserving his uncertainty about timing.Open in transcript →
Quote“LOOKING BACK NOW I'M DISAPPOINTED IN THE LEVEL OF TRANSPARENCY.”— James MattisMattis gave his retrospective assessment of the information supplied to him as a director.Open in transcript →
Quote“THERE ARE SOME THINGS THAT YOU DON'T WANT TO ROLL OUT AS A PROTOTYPE THAT ISN'T PROVEN AND DEALING WITH PEOPLE'S LIVES, HEALTH CARE, THAT WOULD BE ONE OF THEM.”— James MattisMattis said he would have supported delaying commercial use and raising more money rather than releasing unproven healthcare technology.Open in transcript →
CrossJames Mattis — CrossJames MattisKevin M. Downey1highlight314lines spoken

Summary

James Mattis acknowledged his limited technical expertise, board compensation, and reliance on others while describing demands for comparison testing, board validation efforts, and the response to criticism of Theranos.

Highlights (1)

admissionMattis agreed that he lacked clinical-laboratory, scientific, and engineering expertise and depended on others to evaluate Theranos's technology.Open in transcript →
RedirectJames Mattis — RedirectJames MattisJohn C. Bostic1highlight23lines spoken

Summary

James Mattis clarified that proposed military testing was never completed, described the board assumptions behind his support for Theranos, and said repeated surprises and insufficient transparency later left him unsure what to believe.

Highlights (1)

testimony highlightMattis said the board would have had concerns about commercial rollout if told the Edison could perform only a small portion of Theranos's testing, and he described his good-faith assumption that Theranos results came from a Theranos machine.Open in transcript →

Day 16

Day 21

DirectDaniel Edlin — Direct (Resumed)Daniel EdlinJohn C. BosticMentioned

Summary

Daniel Edlin distinguished Theranos's military research, evaluation, and cybersecurity testing from clinical deployment, contrasted presentation claims with his limited knowledge and demonstration experience, and described Holmes's role in military planning, resource allocation, and decision-making alongside Ramesh Balwani.

Mentioned in this proceeding.

Day 23

Day 28

colloquyCMS Report and Voided-Test Evidence ColloquyMentioned

Summary

The parties disputed the admissibility and scope of the CMS report and Kingshuk Das's anticipated voided-test testimony. The court ordered a written prosecution proffer by midday Monday and scheduled argument for Tuesday morning without deciding admissibility.

Mentioned in this proceeding.

Day 29

Day 35

Day 36

ProceduralMotion to Exclude Fabrizio Bonanni Testimony and Late DisclosuresMentioned

Summary

The government sought to exclude Fabrizio Bonanni's proposed testimony based on relevance and late disclosures. The defense argued that his knowledge of Minilab capabilities and Holmes's later conduct bore on intent. The court raised foundation, hearsay, discovery, and scheduling concerns but issued no exclusion ruling.

Mentioned in this proceeding.

DirectFabrizio Bonanni — DirectFabrizio BonanniKatherine TrefzMentioned

Summary

Bonanni explained the Minilab through demonstratives and described Theranos's 2016 board debates, regulatory strategy, and quality and compliance reforms. He praised Holmes's receptiveness to advice but identified operational focus and regulatory execution as weaknesses; several proposed opinions were excluded.

Mentioned in this proceeding.

Day 39

DirectElizabeth A. Holmes — DirectElizabeth A. HolmesKevin M. DowneyMentioned

Summary

Holmes described Theranos's military projects, demonstrations, laboratory oversight, and regulatory history before giving emotional testimony alleging coercion and sexual abuse by Ramesh Balwani. She denied that Balwani forced her investor or press statements, addressed the 2015 CMS failures and later remediation, and said she never sold her Theranos shares.

Mentioned in this proceeding.

Day 40

Day 42

RedirectElizabeth A. Holmes — RedirectElizabeth A. HolmesKevin M. DowneyMentioned

Summary

Holmes used redirect to explain Theranos's laboratory oversight, modified analyzers, financial projections, partner reports, trade-secret restrictions, and responses to Tyler Shultz. She attributed operational and technical work to others while acknowledging authority over investor presentations and explaining nondisclosure of modified systems as trade-secret protection.

Mentioned in this proceeding.

Day 47