What Not to Say in an HR Investigation: Guide for Interviewers and Witnesses

6/3/2026

An investigation can be procedurally perfect and still collapse because of a single sentence spoken in an interview room. Some of the most damaging statements come from well-meaning investigators trying to be reassuring — and every one of them will be quoted back verbatim.

Quick answer: Investigators must avoid promising confidentiality, prejudging outcomes, revealing information across witnesses, issuing blanket gag orders, or offering personal opinions. Witnesses should avoid speculation, secondhand narrative presented as fact, and discussing the interview afterward. Both should stick to firsthand, specific, verifiable information.

Part One: What Investigators Must Never Say

1. "This is completely confidential."

It is not, and you cannot make it so. Information must be shared with decision-makers, may be disclosed to the accused as a matter of fairness, and may be produced in litigation or an agency proceeding.

Say instead:"We'll share what you tell me only with people who need to know in order to complete this investigation and make a decision. I can't promise complete confidentiality, but I can promise we'll handle it carefully and only share what's necessary."

2. "Don't discuss this with anyone."

Blanket confidentiality instructions to witnesses have drawn scrutiny under the National Labor Relations Act, which protects employees' right to discuss terms and conditions of employment. Instructions must be justified by the circumstances of the specific investigation.

Say instead:"I'm asking you not to discuss this conversation with other people involved while the investigation is open, so we can get everyone's independent recollection and protect the people who came forward. That request applies to this investigation, and I'll let you know when it's concluded. You're free to discuss your own working conditions generally, and nothing here limits your right to talk to a government agency."

3. "I'm sure this is all a misunderstanding."

Any statement expressing a view about the outcome before evidence is gathered destroys the appearance of neutrality — and neutrality is the entire value of an internal investigation.

Say instead:"I don't have conclusions at this point. My job is to gather information from everyone involved and then assess it."

4. "Three other people already told me the same thing."

Revealing other witnesses' statements contaminates recollection, discourages candor, and gives the impression of a coordinated case. It also destroys the independent-corroboration value of the testimony you have already gathered.

Say instead:"I'd like to hear your own recollection, in your own words, without me framing it."

5. "You have nothing to worry about" / "Nothing will happen to you."

You cannot guarantee an outcome. What you can guarantee is a process and protection from retaliation.

Say instead:"Retaliation for participating in this investigation is prohibited, and we take that seriously. If you experience anything you think is retaliation, contact me directly. I can't tell you what the outcome of the investigation will be, but I can tell you the process will be fair."

6. "Why didn't you report this sooner?"

Asked in that tone, this is read as blame. Delay is often relevant, but the framing must be neutral and non-accusatory.

Say instead:"Help me understand the timeline. Walk me through what happened between the incident and when you came forward."

7. "In my opinion, that's harassment."

Investigators gather facts. Legal conclusions belong to counsel and to decision-makers, and an investigator's premature characterization can bind the organization.

Say instead: nothing. Record the facts and let the finding follow the evidence.

8. "Off the record…"

There is no off the record in a workplace investigation. Offering it invites information you then cannot use and creates an appearance of side dealing.

9. Leading questions of any kind

Leading (avoid)	Open (use)
"He made you uncomfortable, didn't he?"	"How did you react?"
"So this happens all the time?"	"How often have you observed this?"
"You saw him touch her arm, right?"	"What did you see?"
"Would you say the environment is hostile?"	"Describe what the working environment has been like."

10. "We'll let you know the outcome."

Be precise. The complainant is generally entitled to know that the investigation concluded and that appropriate action was taken; they are usually not entitled to know the specific discipline imposed on another employee.

Part Two: What Witnesses Should Avoid

Provide these guidelines to witnesses at the start of the interview. They improve evidence quality and reduce the risk of the witness creating problems for themselves.

• "I think he was probably drinking." If you did not observe it, say you did not observe it. "I don't know" is a complete and valuable answer.
• Secondhand information presented as firsthand. Say explicitly: "I didn't see this — Maria told me about it."
• Characterizations instead of facts. "He's a bully" tells the investigator nothing. "He raised his voice and told her she was useless in front of six people on March 3" is evidence.
• Editorializing about the parties. Opinions about someone's character are not relevant and undermine the witness's credibility.
• Guessing at dates or numbers. Approximate honestly: "sometime in early spring, I think March or April."
• Discussing the interview with others afterward. This is the most common way investigations get contaminated.
• Withholding unfavorable information. Partial accounts that later unravel do more damage than the original facts.

The Opening Statement That Prevents Most Problems

Read a consistent opening to every witness. It sets expectations, satisfies several legal obligations at once, and can be documented as having been given:

"Thank you for meeting with me. I'm looking into a concern that was raised, and I'm speaking with several people. A few things before we start.

I'm here to gather facts, not to reach a conclusion today. I'd like you to tell me what you personally saw, heard, or experienced. If you don't know something, please say so — 'I don't know' is a good answer. If something is secondhand, please tell me who you heard it from.

I'll share what you tell me only with people who need to know to complete this process. I can't promise complete confidentiality. I'm asking you not to discuss this conversation with others involved while the investigation is open, so everyone's recollection stays independent.

Retaliation against anyone who participates is prohibited. If you experience anything you believe is retaliation, tell me right away.

I'll be taking notes. Do you have any questions before we begin?"

Documentation: What to Write and What Not To

• Write: date, time, participants, questions asked, answers in the witness's own words wherever possible, documents reviewed, follow-up items.
• Do not write: your impressions of credibility as conclusions ("she was clearly lying"), legal conclusions, speculation, or commentary about parties not relevant to the allegation.
• Credibility assessments belong in the report, expressed against articulated factors — plausibility, demeanor, motive to falsify, corroboration, past record — not as offhand notes.

See our guides to HR investigation documentation best practices and interview techniques for HR investigators.

Frequently Asked Questions

Can we require witnesses to keep an investigation confidential?

Instructions must be justified by the circumstances of the specific investigation — such as protecting witnesses, preventing evidence destruction, or avoiding contamination of testimony — rather than imposed as a blanket rule. Document the justification.

Should investigators record interviews?

It depends on jurisdiction, policy, and consent requirements. Detailed contemporaneous notes reviewed with the witness are the more common practice. Whatever you choose, apply it consistently.

Can a witness bring someone to the interview?

In a unionized workplace, an employee who reasonably believes discipline may result has the right to request union representation at an investigatory interview. Non-union employees generally do not have an equivalent right — see our guide to Weingarten rights.

What if a witness refuses to participate?

Document the refusal. Employees may generally be required to cooperate in workplace investigations as a condition of employment, but pressure should be applied carefully and never in a way that appears coercive to a complainant.

Should the accused be told who complained?

The accused must know the allegations well enough to respond meaningfully, which often makes the source apparent. Weigh fairness against the risk of retaliation, and document the reasoning.

Train Investigators Before They Sit Down

Investigation skill is not intuition. The difference between a defensible finding and a settlement is usually a handful of learned techniques applied consistently.

The Internal Investigations Certificate Program covers interviewing, evidence handling, credibility assessment, and report writing. Experienced investigators handling complex or high-exposure matters should look at the Advanced Internal Investigations Certificate Program, and self-paced learners at the Online Internal Investigation Training & Certification Course.

👉 See the Workplace Investigation Training Program →

Additional resources: Workplace Investigations FAQs | How to Do an Internal Investigation | Glossary of Workplace Investigation Terms