Check It Out Verification Rule
Verify claims through primary evidence before publishing or deciding
- Difficulty
- Moderate
- Time to result
- ~weeks to results
- Steps
- 6
- Confidence
- 94%
The rule converts an interesting claim into a verified conclusion through disciplined checking. Begin by treating tips, intuition, and public narratives as leads rather than proof. Find people with direct access to the relevant events, earn their trust, and determine whether their knowledge is firsthand. Corroborate important allegations through additional sources, documents, technical evidence, or observable results. Then present precise questions to the subject so genuine counterevidence can surface. Threats, secrecy claims, and reputational pressure must not substitute for factual answers. The final output should include only conclusions supported by the accumulated evidence. Carreyrou's early reporting failure illustrates the cost of skipping this process, while his Theranos investigation shows how persistence, corroboration, and careful right-of-reply procedures can withstand an aggressive challenge.
Origin
Carreyrou learned the rule after publishing an erroneous early-career story based on sources several steps removed from the supposed deal. He later recognized the same principle in Seymour Hersh's account of the City News maxim “check it out.”
Core principles
- 01Treat unverified information as a lead, not a fact
- 02Trace claims back to people with direct knowledge
- 03Corroborate consequential allegations with independent evidence
- 04Give the subject a fair opportunity to respond
- 05Keep digging when intimidation replaces substantive answers
How to run it
- 1
Treat the Claim as a Lead
Record what has been alleged without accepting it as established fact. Identify precisely what would need to be true for the claim to hold.
Pro tip Write the core claim as a testable sentence.
Watch out Initial plausibility or a trusted introduction is not verification.
- 2
Reach Primary Sources
Find people who directly observed, performed, or documented the relevant activity. Establish why each person is positioned to know what they claim.
Pro tip Use professional networks and public tools to locate former insiders.
Watch out Sources several times removed from the facts may confidently repeat fiction.
- 3
Build Trust and Corroboration
Protect vulnerable sources appropriately and compare their accounts with independent testimony or records. Look for agreement on material facts rather than identical wording.
Pro tip Start with facts that can be independently checked to assess source reliability.
Watch out Do not allow one compelling source to become the entire scaffolding of the case.
- 4
Demand Demonstrable Evidence
Request documents, data, physical demonstrations, or tests that could validate the claim. Distinguish evidence of actual performance from presentations, simulations, and prerecorded outputs.
Pro tip Control the test conditions whenever possible.
Watch out A demonstration managed entirely by the claimant may be theatrical rather than probative.
- 5
Offer a Specific Right of Reply
Send the subject detailed questions and enough information to address the material allegations. Evaluate whether the response supplies evidence or merely invokes secrecy, attacks motives, or threatens consequences.
Pro tip Ask narrow questions that cannot be answered with promotional generalities.
Watch out Do not mistake legal aggression for factual rebuttal.
- 6
Publish the Supported Case
Remove claims that remain inadequately supported and clearly distinguish established facts from uncertainty. Continue checking and correcting the record as new evidence emerges.
Pro tip Preserve a source-and-document map for every major assertion.
Watch out The desire for impact must never outrun the evidence.
In the wild
Early in his career, Carreyrou and a colleague reported a supposed merger involving European postal services. Their sources were several steps removed from the alleged deal, and the reporters did not independently check whether it existed. The deal was fiction and the resulting story was erroneous.
→ The failure produced a durable rule: verify claims rather than repeating the first plausible account.
Carreyrou combined a pathologist's skepticism with information from former laboratory director “Alan Beam,” Tyler Schultz, Erika Cheung, doctors, and other insiders. He sought answers from Theranos, allowed the company to respond, and continued checking despite threats against sources and the newspaper.
→ The corroborated reporting survived legal pressure and exposed the Theranos scandal.
Common mistakes
Publishing the First Plausible Account
A confident source can still be wrong, especially when removed from the underlying event. Treat the first account as a starting point for checking.
Confusing Secrecy With Evidence
Claims of trade secrecy may explain limited disclosure, but they do not prove that a product or capability exists. Seek independently testable evidence.
Letting Pressure Destroy the Investigation
Threats can frighten sources and weaken corroboration. Protect the evidentiary scaffolding by developing multiple sources and maintaining careful records.
Is it for you?
Best for
It is best for journalists, analysts, investors, and leaders evaluating disputed or high-stakes claims.
Not ideal for
It is not ideal for trivial decisions where exhaustive verification would cost more than an error.
From the transcript
“you can't you you got to verify.”
“And we didn't do any checking. We just went with what you know, the first person we got on the phone told us and the…”
“it's uh work that requires persistence and perseverance.”
From the episode
John Carreyrou on Breaking Open the Theranos Scandal
John Carreyrou