Conducting Workplace Investigations Without a Participating Complainant: Practical Tips for Investigators
Workplace investigations present unique challenges even under ideal circumstances. But when a complainant chooses to remain anonymous, or a known complainant simply declines to participate, those challenges multiply. Without the benefit of the complainant’s account, investigators must work harder to prepare an investigative plan, define the scope of the investigation, gather evidence, build a credible witness list, and produce a report that can withstand scrutiny. The following tips are designed to help investigators navigate these situations with rigor and professionalism.
1. Use the Anonymous Reporting Hotline as a Two-Way Channel
Many anonymous complaints come through an organization’s reporting hotline. Complainants may think of these tools as one-directional — a way for employees to raise concerns without being identified. But most of these platforms also allow for communication with the complainant.
If a complaint comes through an anonymous hotline, consider using that same channel to respond. Respond to the complainant, letting them know you take their complaints seriously and attach your anti-retaliation policy. Employees who report anonymously are often doing so out of fear of retaliation. Reminding them of their protections for raising complaints can address some of those concerns and may encourage the complainant to engage further.
Even if the complainant ultimately elects to remain anonymous and declines to sit for an interview, a response through the hotline can yield meaningful information. The complainant may be willing to respond to limited written questions. The complainant may be willing to list witnesses the complainant believes have relevant knowledge and documents, communications, or other records that may be helpful.
You can also use this approach with a known complainant who refuses to sit for an interview. Some such complainants are unwilling to meet with an investigator but are willing to share written information, documents, or suggest witnesses.
2. Build Your Witness List Thoughtfully — and Defensibly
In a typical investigation, the complainant provides an initial roadmap: a list of witnesses and documents, relevant time periods, and key events. When that roadmap is unavailable, the investigator must construct a witness list independently.
Without the complainant’s input, thoughtful witness selection requires examining organizational charts, reviewing relevant communications, and identifying employees who, by virtue of their role or proximity to the relevant events, are likely to have useful information. In some cases, particularly those in which the relevant conduct may have affected a broader group of employees, consider selecting a randomized sample of potential witnesses. For example, if the respondent allegedly made comments to a class of college freshman, obtain a class roster and use a random number generator to select a group of students from it. In certain investigations, it may make sense to select a random sampling that is balanced in terms of gender or race. This approach can demonstrate that the investigator cast a wide, impartial net and did not cherry-pick favorable voices.
Document your selection methodology clearly — it is a critical part of your report to show your good faith process in reaching findings.
3. Document Your Process — Not Just Your Findings
Every investigation report should explain what evidence you gathered, or were unable to gather, and why. This is always good practice, but it becomes especially important when the investigation is conducted without a participating complainant.
Use your report to walk the reader through your methodology: how you identified witnesses, how you selected documents for review, what databases or systems you searched, and why you made the evidentiary choices you did. It should also include other decisions you made, such as whether you considered doing a forensic review of emails or text messages; whether you sought video surveillance or did a site visit; whether you employed a workplace climate review; and any other investigative techniques that demonstrate your thoroughness in uncovering evidence related to the complaint.
This transparency not only strengthens the integrity of your findings — it also provides a clear record that can be defended if the investigation is later challenged.
4. Acknowledge the Complainant’s Non-Participation in Your Report
When a complainant declines to participate, document that fact in the report. Your report should describe the steps taken to secure the complainant’s participation: how they were contacted, through what channel, and on how many occasions. It should note that the complainant declined and that, as a result, the investigation was conducted without the benefit of their first-hand account. If the complainant’s non-participation required you to make additional investigative efforts — such as expanding your witness list or conducting a more exhaustive document review — say so. Framing these efforts appropriately helps explain why the investigation was thorough despite its constraints, and it provides important context for any factual findings or credibility assessments that follow.
A Few Final Thoughts
Investigations without a participating complainant are harder, but they are not impossible to conduct well. The keys are creativity in gathering information, rigor in selecting evidence, and transparency in explaining your process. Investigators who approach these cases with discipline and document their methodology carefully are far better positioned to produce findings that are credible, defensible, and fair to all parties.
