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Workplace investigations — Federal

The importance of investigating employee complaints

Employers often conduct workplace investigations because of constitutionally or statutorily imposed requirements. Indeed, various civil rights and anti-discrimination laws, as well as health and safety laws, require employers to investigate complaints or accidents and take appropriate remedial action. Thus, after a written or oral complaint is made by an employee regarding improper conduct, an affirmative duty may arise requiring the employer to investigate the allegations. As discussed herein, investigation of complaints yields a number of additional, practical benefits for employers as well. Even when no official complaint is made concerning improper conduct, an employer may be under a duty to investigate if the employer has “constructive knowledge” (reasonably should have known) of that conduct.

Defense to charge of harassment/hostile environment

It is critical for an employer to investigate claims of unlawful harassment, as an investigation can be used as an affirmative defense to a hostile environment harassment charge. In other words, even if harassment occurred, a strong anti-harassment policy, an effective investigation and a prompt and effective remedial measure may well prevent the employer from being liable. Generally, the plaintiff in a potential lawsuit against the employer must show that the employer knew or should have known about any harassment that is the basis for the lawsuit. If the employee did not complain to management, he may not be entitled to pursue a claim. Likewise, if the employee complained and the employer took prompt and effective remedial action, then the employer might also have a defense to the unlawful harassment complaint.

Limit liability for discrimination or sexual harassment

An investigation may also limit the employer’s liability for discrimination or hostile environment unlawful harassment. Although employer knowledge and prompt remedial action are not defenses to disparate treatment discrimination claims or to “tangible employment action” sexual harassment claims, a proper investigation can still limit employer liability. If the employer immediately investigates any claims of discrimination, it may stop the discrimination and thus limit the amount of the plaintiff’s damages – especially punitive damages. Also, the employer may be able to limit the scope of the lawsuit to only those issues that the plaintiff/employee raised during the internal investigation by later raising the defense that the employer was not on notice of other claims and the employee should be limited from expanding his claims.

Limit claims relating to negligent retention

In addition, an investigation can limit claims relating to negligent retention. If an employee is harassed or discriminated against, he or she may bring state law claims alleging that the employer negligently retained someone that it knew or should have known was a sexual harasser or discriminator. Such a claim would be strengthened if the plaintiff could show that the employer had received several complaints about the individual who harassed or discriminated against him. Thus, an employer who has a policy and a practice of investigating every claim of harassment or discrimination is in the best position to defend a subsequent lawsuit for negligent retention. Alternatively, the employer could also argue that it had no reason to know that this particular person had a tendency to harass or discriminate.

Create a more agreeable workplace

Generally, a proper investigation policy fosters a less litigious workforce. Employees who feel that the employer takes their complaints seriously and investigates their complaints will be less likely to sue later. Many times, a plaintiff will say that if the employer had just treated her right after she raised her complaints, she wouldn’t be in court today. Investigations are beneficial for the employer generally because when a complaint is filed, even if no sexual harassment is found, the employer knows to keep an eye on the accused individual for possible future transgressions.

Investigation is a good source of information about the complaint

Finally, an investigation is the employer’s first and most reliable source of information about the complainant’s allegations. Based on the investigation, the employer will be better able to make decisions about what remedial action or disciplinary action should take place. Also, if a lawsuit ever arises out of the complaint, the investigation better protects the employer. The employer will also be in a better position to determine whether to offer to settle the case and whether to represent or indemnify an individual manager or employee accused of harassment or discrimination.

The mechanics of internal investigations

Determining if a complaint has been made

An employee has raised a complaint of harassment or discrimination

any time he or she makes such an allegation to anyone in the human resources department or to any manager or supervisor. In particular, managers must be reminded to report any complaint of harassment, discrimination or retaliation for a prior complaint to human resources, no matter how minor it seems or how informally it was raised. Managers should not investigate such complaints on their own. It is important for managers (and everyone in the employer organization) to remember that in the long run, it will be better for the employer to uncover the truth regarding such allegations.

Receiving complaint

When a complaint is made, a productive initial conversation with the complainant is a critical first step in determining whether an official investigation may be necessary. Likewise, obtaining a complete and accurate statement regarding the complaint is essential to a determination as to the extent of the investigation required. The following steps should be taken promptly in order to ensure that an investigation is effective. 

Instruct the complainant

The complainant should be told that his complaint is treated very seriously by the employer and that it will be investigated pursuant to employer policy (and describe any applicable policy). The complainant should also be told that he will not be subjected to adverse action for coming forward and that the complainant should contact the investigator immediately if he feels that he is being retaliated against for any reason. Finally, the employee delivering the complaint should be told not to discuss the matter with others and that, while the investigation will be treated confidentially, the investigator will discuss the matter with those necessary to the investigation or any action taken as a result of the investigation.

Have a signed, dated complaint


  • who harassed/discriminated against the complainant (including the name and work relationship to complainant)
  • what that person did (Include specific statements, improper conduct that is the subject of the complaint and any reasons that the complainant may believe prompted the conduct.)
  • where and when the conduct took place (including the first time, each subsequent time and the last time the conduct took place)
  • how the complainant responded (Did the complainant indicate the conduct was objectionable? Did anyone else?)
  • witnesses to the harassment/discrimination. Have the complainant identify the witnesses’ names and what the witnesses may have seen or heard. In addition, ask the complainant whether he told anyone about the improper conduct.

Take detailed notes of the conversation

Include the name of the interviewer, date, time and location of the interview, who was present and length of the interview. This document may become an important piece of evidence in the event that the complainant or the alleged wrongdoer sues the employer. Accordingly, it is important that the interviewer document only the facts as stated by the complainant and not his opinions or conclusions about the interview.

Gauge expectations

Asking the complainant about the outcome he hopes to achieve as a result of the complaint may set him up for disappointment. At this stage, the employer may decide there is no need to ask such questions. However, the employer may want to know what the complainant expects to happen. This information is often helpful in gauging how serious complainant believes the conduct is. But, if the employer intends to ask, they must make clear to the complainant that the outcome will be based upon the information learned in the investigation and upon the company’s view of how best to address what is learned, which may or may not be consistent with the employee’s wishes.    

Do not make promises or offer opinions

  • Do not promise complete confidentiality, but only confidentiality consistent with an effective investigation.
  • Do not promise that the alleged wrongdoer will not come to know of the complaint.
  • Do not promise to keep the complainant’s identity a secret from the alleged wrongdoer.
  • Do not tell the complainant whether he or she is believed.
  • Do not promise that the alleged wrongdoer will be disciplined.
  • Do not discipline the complainant for reporting the complaint

Even if the complainant has complained to the wrong person or gone “outside the chain of command,” do not indicate that the complaint could result in any sort of discipline for the complainant. This may be considered retaliation. However, the anti-harassment policy should provide for discipline in the event of a false report. The employer should not hesitate to take corrective action, consistent with the policy, for an improper use of the reporting mechanism.

Identifying an investigator

Determining whether to engage an internal or external investigator is a very important decision with many legal ramifications. The chosen investigator must be well-trained and impartial. A wrongly chosen or biased investigator may discourage candid interviews or even the reporting of illegal conduct. An employer should choose an investigator who is experienced, properly trained and objective. Generally, an employer should have several qualified and trained investigators within the company and may engage more than one investigator in any one investigation. It is important to remember that everything that the employer does to investigate a claim of discrimination or harassment may be admissible in a lawsuit. Thus, the written materials may be obtained by the plaintiff and the person who conducted the investigation may be called upon to testify. If the investigation is conducted at the request or recommendation of an attorney, the employer may be able to make an initial argument that the investigation is protected by the work product doctrine or the attorney-client privilege. However, courts generally will not give this argument much merit.

There are several potential investigators available to the employer. The first is an uninvolved manager. Although the complainant and the accused may open up to a person with whom they are more familiar, it is usually not a good idea to allow an uninvolved manager to investigate. The manager may not know proper procedures and handle the investigation in a way that is harmful to the employer. Also, the manager’s knowledge of the situation may embarrass the complainant or the accused. A more appropriate choice is the employer’s human resources representative. The HR representative should be trained regarding proper procedure and can be impartial, thereby obtaining more accurate testimony from witnesses. However, if the employer uses an HR representative, the work will be discoverable. Another choice is an in-house attorney or outside attorney. Either one can be properly trained regarding procedure, impartial, more familiar with legal ramifications and can better handle accusations against high-level managers. However, the use of an attorney may force the employer to waive privilege, exposing legal advice to discovery. Also, an outside attorney operating as a fact witness will be precluded from representing the employer in any lawsuit arising from the complaint. The smartest choice for the employer would be to obtain an outside consultant. The consultant can be properly trained to handle the situation, will be impartial, will be familiar with legal ramifications and will be able to deal with accusations against high level managers.

Initial discussion with the alleged wrongdoer

It is advisable to have two people interview the alleged wrongdoer in order to ensure that there is a witness to the discussion and, specifically, to any remarks that the alleged wrongdoer may make. If the alleged wrongdoer is a member of a collective bargaining unit, then he or she is entitled to have a union representative present during any interviews or investigations of him or her. However, the employer does not have to offer the alleged wrongdoer such representation unless he or she requests it.

The initial interview of an alleged wrongdoer is a critical part of the investigation and he should be told that the employer takes the allegations of his conduct seriously by fully investigating them consistent with its policy. The interviewer should inform the alleged wrongdoer of the allegations against him and review relevant employer policies with him. In addition, the alleged wrongdoer may be told that there is a possibility of disciplinary action if the complaint is found to be true, but that he or she will be given an opportunity to respond to all allegations and that the employer has not yet determined that the alleged wrongdoer is guilty. It is important to remember that if the alleged wrongdoer is an employee the employer cannot require, request or suggest that the individual submit to any lie detector test.

Instruct the alleged wrongdoer to minimize immediately contact with the complainant and warn the alleged wrongdoer that they may be separated during the investigation. The alleged wrongdoer should be given a strict warning not to retaliate against the complainant and instructed to keep the matter confidential in order to protect his privacy, prevent rumors and protect the integrity of the interview process. Finally, the alleged wrongdoer should be advised that if he violates any of these instructions, the employer will consider it insubordination and possible grounds for termination.

Identifying witnesses and relevant documents

It is important to interview all individuals involved with the complaint, including all witnesses identified by the complaining employee. Companies should also consider interviewing all employees who work closely with the accused. However, be careful interviewing non-employee witnesses, as they are less likely to keep the matter private and may be less reliable. Schedule meetings at a time and place so that the meetings will not attract attention. Explain the need for confidentiality to the witnesses and ask questions designed to discover the who, what, when, where and how of the situation. Document all interviews, keeping in mind that this documentation may be admissible in a future lawsuit, so be careful of making unsubstantiated statements or hasty opinions. Be sure to talk to both the accused and the complainant. If the investigation lasts more than two to three days, follow up with the complainant and keep them informed of the investigation, assuring the complainant that the employer is looking into the matter.

Next, collect any relevant files, documents or statistics that may help verify or disprove the allegations. In a sexual harassment case, for instance, review any notes, calendars and diary entries maintained by the complainant, including correspondence between the complainant and the accused or the complainant’s friends or supervisors. Employers should also acquire the personnel file of the accused, desk files maintained by the supervisor of the accused and investigation or discipline files for other individuals accused of similar conduct.

In a disparate treatment case, obtain and review certain files or records regarding employees who are “similarly situated” with respect to the complainant. Generally, the complainant will identify several individuals outside of the protected classification who he believes have been treated better than he has. The employer should pull the files of those individuals, as well as employees whom the complainant’s supervisors feel are similarly situated to the complainant. Files the employer may need to review include:

  • personnel files
  • payroll or compensation files or records
  • hiring, promotion or transfer records
  • evaluation forms
  • reduction in force plans or termination statistics.

Employer rules, policies, procedures and instructions should also be reviewed in most investigations.

Immediate, temporary steps to stop any wrongdoing

If the investigation will take more than one day, take immediate steps to deal with the alleged wrongdoing – particularly any harassment.


  • giving the complainant the option of taking paid leave from work
  • giving the complainant the option of moving to a different work location on a temporary basis
  • instructing the alleged wrongdoer not to talk to the complainant
  • changing the supervisory reporting structure.

Be careful to avoid the appearance that the alleged wrongdoer has already been deemed guilty of the offense.

Preparing the investigation file and log

The investigation file should be complete, accurate and thorough. It is important to include:

  • a chronology of events
  • a list of all people involved or contacted
  • a list of all documents reviewed
  • all communications with those involved
  • witness statements
  • documents that establish or refute the issues investigated
  • physical evidence
  • investigator’s reports
  • documentation of results or remedial actions
  • a summary of the allegations and responses
  • a complete record showing the employer’s prompt and appropriate action.

Companies should not include conclusions about credibility or the merits of the complaint, as the file may be admissible in a later lawsuit. Instead, the file should only contain objective, fact-finding information.

Investigation files usually include a log of the investigator’s actions. Keeping the complaint logged is a good way to keep track of complaints within a changing workplace. The log also makes the employer aware of multiple claims against the same person or within the same group. The log should include:

  • date of the initial complaint
  • name of the victim
  • type of claim
  • name of the accused
  • department/division involved
  • level of complaint (such as, internal-informal, internal-formal grievance, lawsuit)
  • resolution and date
  • person assigned to investigate.

It is crucial to always keep the log confidential.

Concluding an investigation

As a consequence of the investigation, the investigator should reach one of three conclusions concerning a complaint or wrongdoing:

  1. that the wrongdoing actually occurred
  1. that the wrongdoing complained of did not occur
  1. if the employer is truly unable to determine whether the wrongdoing occurred, it can find that the evidence was inconclusive.

A determination that evidence is inconclusive, however, should not be used as a means of avoiding a difficult decision.

In determining whether the complained-of conduct occurred, the investigator should evaluate the credibility of all witnesses, considering whether the complainant’s story or the alleged wrongdoer’s story is consistent with the stories provided by other witnesses. The investigator should determine whether the complainant and the alleged wrongdoer were cooperative or appeared to be withholding information and consider whether the complainant or alleged wrongdoer exhibited characteristics of lying (failure to make eye contact, squirming, internally inconsistent story, lack of details). In addition, an investigator might consider the past history of the complainant and the alleged wrongdoer. Even if past complaints against the alleged wrongdoer were investigated and found to be inconclusive, multiple complaints may indicate that the current complaint is true.

Finally, the employer must document any decision reached. Documentation should include a review of the complaint, each witness’s version of the facts and the employer’s conclusion with an explanation for its reasons.

Closing the investigation

Once a conclusion is reached about what occurred, the employer must take swift, appropriate action including but not limited to discipline, termination, warning or conclusion of the investigation without action. It is usually a good idea to separate the investigation function from the task of deciding what to do with the results. Someone in human resources is much more likely than an outside investigator to understand the effects of particular remedial action in the workplace and to ensure that the company is treating cases of similar severity in a similar manner. For this reason, it may be beneficial to request that an outside investigator not make any recommendations in the initial report. Once someone from human resources reviews the factual conclusions of the investigation, the investigator can be questioned about any remedial actions that might be contemplated. Any documentation issued to close out the investigation, whether or not discipline is issued, should remind all parties that the company’s policy prohibits retaliation and any suspicions of retaliation should be reported and investigated promptly. It is also helpful at this stage to review the company’s applicable policies with everyone involved in the investigation.