Workplace Investigations: Avoiding this Litigation Landmine

Poorly conducted workplace investigations are one of the leading causes of employment litigation. Common mistakes include delaying the start of an investigation, using an investigator who lacks impartiality or training, failing to interview all relevant witnesses, not documenting findings thoroughly, and reaching conclusions before gathering all the facts. Allowing the accused to learn details of the investigation prematurely can lead to witness tampering or retaliation. Conversely, taking adverse action before completing the investigation exposes employers to wrongful termination and discrimination claims. Another frequent error is treating similar complaints inconsistently—investigating some while dismissing others. Organizations that invest in training HR professionals and managers on proper investigation protocols, and that follow a disciplined, documented process every time, dramatically reduce their litigation exposure and demonstrate good faith compliance with anti-discrimination laws.

The investigator must be impartial, trained, and have no personal stake in the outcome. For most internal complaints—such as harassment, discrimination, or policy violations—a trained HR professional can conduct the investigation, provided they have no personal relationship with either party and can genuinely remain neutral. For senior-level complaints, complaints against HR staff, or particularly complex or high-stakes matters, engaging external legal counsel or a third-party investigator is often the better choice. External investigators bring both independence and legal privilege protections that internal staff cannot. Regardless of who conducts the investigation, the investigator should have a clear understanding of investigative techniques, interview methodology, evidence collection, and documentation standards. Many organizations also designate a small team of trained internal investigators to ensure consistent practices across all complaint types.

A sound workplace investigation follows a structured process. First, assess the complaint promptly and determine whether interim protective measures—such as temporary reassignment or paid administrative leave—are needed to prevent ongoing harm or retaliation while the investigation proceeds. Second, plan the investigation: identify witnesses, relevant documents, and communication records. Third, conduct interviews in a logical sequence—typically the complainant first, then key witnesses, and finally the respondent. Use open-ended questions and detailed note-taking. Fourth, gather and preserve all relevant physical and electronic evidence. Fifth, assess credibility and weigh the evidence to reach a finding on the balance of probabilities. Sixth, document findings in a written report. Finally, communicate outcomes appropriately to the parties and implement any remedial measures. Maintaining confidentiality throughout—sharing information only on a need-to-know basis—is critical to legal defensibility.

Retaliation claims are among the most frequently filed employment charges—and they often arise even when the underlying complaint is not substantiated. Employers must take concrete steps to prevent retaliation throughout the investigation process and afterward. This starts with clearly communicating to all parties that retaliation is prohibited and will result in serious discipline. Monitor the working relationship between the complainant and respondent during and after the investigation for any changes in treatment, assignments, or performance evaluations that could be perceived as retaliatory. Document any legitimate, business-based reasons for any adverse employment actions taken after a complaint is filed. Train all managers on what constitutes retaliation—even subtle changes in treatment can meet the legal standard. A no-retaliation policy should be conspicuously posted, reinforced in training, and enforced consistently. Prompt remediation of retaliation when it occurs is essential to limiting damages.

Several scenarios warrant involving outside legal counsel in a workplace investigation. When the complaint involves a senior executive or a member of the HR team, internal objectivity is compromised and an outside attorney can provide needed independence. When the allegations are particularly serious—sexual assault, systemic discrimination, significant financial misconduct—outside counsel brings both investigative rigor and legal privilege protections. Complaints that are likely to result in litigation or regulatory agency charges (EEOC, NLRB) benefit from the attorney-client privilege that attaches when legal counsel directs the investigation. High-profile or media-sensitive complaints also call for outside expertise. Employers should consult with employment counsel at the outset of any investigation where the potential liability is significant, using counsel's involvement to shape the investigation strategy and ensure findings are thoroughly documented and defensible in any subsequent legal proceeding.