What Evidence Can Whistleblowers Take?

Kathleen Gallagher · March 5, 2026 · 6-min read

If you uncovered fraud you will need to gather proof that backs up your claim. But it is important to be careful about what and how you collect this evidence. Taking the wrong approach might hurt your case or even get you in trouble. Here is how to do it the right way:

You do not have to take every single document or file you see. Instead, focus on collecting the really important stuff that clearly shows the fraud, like:

• Bills the government was charged for
• Proof of payments made
• Contracts or agreements tied to the fraud

Courts understand that protecting the public means whistleblowers can share certain private info (like medical records) with their lawyer or the government, if it helps prove the fraud. But taking too much unrelated material—like entire folders or hard drives full of random files—can cause legal problems. For example, in Cafasso v. Gen. Dynamics C4 Sys. Inc., 637 F.3d 1047 (9th Cir. 2011), the court upheld a decision that an employee-relator breached her confidentiality agreement when she copied nearly eleven gigabytes of data—tens of thousands of pages—by grabbing whole folders and not reviewing individual documents to determine whether they were relevant to her whistleblower complaint. The Ninth Circuit emphasized that by doing this, the relator swept in sensitive and legally protected material (including privileged communications and trade secrets). This decision underscores why ‘less is more’ when gathering evidence—taking fraud-related documents is protected, but overly broad copying can expose you to lawsuits.

Remember: Only keep documents you reasonably believe are related to the fraud.

Recording conversations can feel like a simple way to preserve what was said, but the laws vary widely and can change depending on whether you are recording an in-person discussion or a phone call. Both scenarios can trigger state “wiretapping” or “eavesdropping” laws; however, phone calls are more likely to be treated as a protected “communication.” In-person recordings can raise different issues—such as whether you placed a device in a room or recorded in a setting where someone reasonably expected privacy—so the fact pattern matters.

A key concept is consent. In a single-party consent jurisdiction, a recording is generally lawful if at least one person in the conversation consents—meaning the recorder can be one of the participants. In a dual-party (also called all-party) consent jurisdiction, everyone on the call or in the conversation must consent before a recording is made. Many states do not apply the same consent rule to phone calls and in-person conversations. If you are unsure which rule applies, do not guess: review your state’s law before you record.

Federal law is often described as a single-party consent framework because the consent of one party to a telephone call is enough under 18 U.S.C. § 2511. But state laws can be more restrictive, and those stricter rules can control in practice. For example, under NRS 200.620, Nevada is an all-party consent state for telephone recordings, which means recording a call is only legal if all parties consent. A practical starting point for checking your state’s rule is this 50-state survey, but treat it as a reference (not a substitute for legal advice) and confirm the current law before you record: https://www.justia.com/50-state-surveys/recording-phone-calls-and-conversations/.

Finally, where the recording happens can also be outcome-determinative. In Ditech Financial LLC v. Buckles, 133 Nev. 493, 401 P.3d 215 (2017), the Nevada Supreme Court held Nevada’s all-party consent statute for telephone calls “does not apply when the act of interception takes place outside Nevada.” The court explained that interceptions and recordings occur where they are made, so the law of the state where the recording was made typically controls, even if the call was received somewhere else. As a result, the court held Nevada law did not apply to recordings of calls with a person in Nevada when the recording party was located and used recording equipment outside of Nevada.

Remember: Never record conversations without knowing the rules that apply to your state.

You should only collect documents you are allowed to see as part of your normal work. For example, if your job lets you see billing records, you can take those. Do not collect files you are not authorized to access, and if you leave the job (or get suspended or fired), do not go back to get information.

Companies often watch computer activity closely. If you suddenly start copying a lot of files, emailing documents to yourself, printing tons of papers, or accessing files you should not be, it could raise suspicion. To avoid this, you can use your personal phone to take pictures of important information on your screen instead of downloading files.

If you talk to coworkers, be very careful! Talking to the wrong person could risk your job or case. Always check with your lawyer before reaching out to anyone.

Finally, if you communicated with your company’s lawyers, those communications may be protected by attorney-client privilege. That means you cannot share those conversations or emails with anyone else, even your own lawyer. A conversation is usually protected if an employee spoke with the company’s lawyer so the company could get legal advice. If you think you have this kind of protected evidence, tell your lawyer without giving the actual details or documents.

Never:

• Access files you do not have permission to see
• Use work email or phones to talk to your lawyer or investigators
• Send or save documents to yourself using company systems
• Record meetings or collect emails with company lawyers

Gathering evidence for a whistleblower case takes planning and care. Follow these tips to protect yourself and make your case stronger. And remember, working closely with an experienced qui tam lawyer is the best way to safely navigate this process and get the best outcome. Contact Gallagher & Lipshutz. Our False Claims Act team can help evaluate your case and map the right path forward.

This post is general information, not legal advice. For guidance on your specific facts, consult experienced False Claims Act counsel.