How to Conduct a Sexual Harassment Investigation (Part 3): Interviewing Witnesses and Obtaining Other Evidence

This post is the third in a four-part series that provides guidance and strategies to HR professionals, managers and business owners on conducting effective sexual harassment investigations. Although this article focuses on sexual harassment, the advice in it applies equally to racial, age-based and other types of harassment investigations.  


A.  Who Else Should Be Interviewed?

Now that you have interviewed the complaining employee and the accused employee, you need to decide whom else to speak with.  You do not want to involve more people than necessary, but you must balance that with conducting a thorough inquiry.  This will largely depend on the nature of the allegations.  If the complaint is “James has made dozens of sexual comments to me and all 10 women in our entire department over the last year,” that will involve more witness interviews than a complaint that “James sent me an inappropriate email.”  The latter may require no additional witnesses at all.

Consider the following when creating your interview list:

  • Potential eye witnesses to the objectionable conduct (including those who were present but saw nothing)
  • Co-workers who have also recently interacted with the accused employee
  • Any employees whom the complaining or accused employee requested that you interview
  • Any “alibi” witnesses identified by the accused employee
  • The accused employee’s supervisor and/or manager

B.  Go Over the Ground Rules.

Each witness should be given an abbreviated version of the ground rules given to the accused employee (see Interviewing the Accused post of March 14, 2013, below), especially emphasizing the need for honesty and full cooperation. 

C.  How Much Information Do You Share?

Many investigators are concerned about sharing too much information with witnesses.  Should you maintain the complaining employee’s anonymity?  Or the accused employee’s?  Should you keep the actual allegations a secret? It is certainly a good idea to use discretion, but you must balance that with your ultimate responsibility under federal law:  to do a prompt and thorough investigation. 

Example:  If Supervisor John is accused of making sexual advances toward Tiffany in the break room, consider how you could conduct a thorough inquiry without identifying the parties.  You could generally ask:  “Did you see anything inappropriate during morning break yesterday?”  But many employees may just say “no,” hoping it will end your questioning, or ask what you mean. In order to nail down what actually happened, you will need to ask if they saw any interactions between John and Tiffany, and if so, what were they. 

D.  What if a Non-Employee is a Potential Witness?

Many companies have contractors or leased employees at their worksites. Sometimes these workers, who may not be your employees, may be important witnesses in a harassment investigation.  The same may be true of employees of an important client or customer.  Should you involve them? 

This depends on how material and critical their testimony is to the case and your company’s internal position on involving outside third-parties.  If a leased worker needs to be interviewed, it makes sense to arrange the interview through the leasing company (in order to avoid, or at least preserve your defenses to, a joint employer situation).  If the worker is employed by your most important client, it may be wise to get approval through the client point-of-contact before approaching the witness directly.

*Note of caution: third-party contractors who your company treats an non-employees can still sue your business for race discrimination under 42 U.S.C. § 1981.  An employment relationship is not a prerequisite for such discrimination claims, as it is under Title VII or most state discrimination laws.  So if the complaining party is a contractor, not an employee, you should still conduct an investigation and put a stop to any inappropriate behavior in your workplace. 

E.  Ask About Hearsay

Many times witnesses will assume you do not want to know about hearsay—things they “heard about” from someone else but did not witness first-hand.  You certainly do want to know about hearsay, and you should ask for it.  Ask “Even though you did not see anything, did you hear about anything that happened?” and “Was there any gossip around the office about what happened?”  Many times this will lead you to additional witnesses with first-hand encounters.


E-mails, text messages and other electronic and written communications can be important evidence in your investigation.  Sometimes they can prove or disprove the allegations of harassment.  How can you obtain this kind of evidence? 

First, remember that you can, and should, simply ask the employee for this evidence.  Many investigators forget this point, or think it is too invasive.  For instance, if Tiffany complains about emails that John sent from his personal email to her personal email, ask her to forward them to you.  If she complains that John sent her inappropriate text messages, ask her to show them to you on her phone (and you can take a picture of them) and/or forward them to your cell phone.  When you interview John, you can first get him to confirm his personal email address and cell phone number, and then ask him questions about the emails and texts Tiffany produced. 

You can and should always ask the accused employee for any “exculpatory” emails and other evidence as well.  For instance, if David is accused of “harassing” Angie by calling her cell phone with work assignments more than any other employee, his cell phone call log may reveal that he called male employees just as frequently.  You should ask to see his call log in order to fully investigate this aspect of Angie’s claim.  

How about obtaining emails from email accounts at work?  Can the employer search those as part of the investigation?  What about reviewing an employee’s internet use?  If the complaint is that John viewed pornography at work, and he denies it, you want to be able to review what websites he has visited. 

The answer to whether you can do this depends on: (1) how your policy is written; and (2) whether the employee received notice and consented to the policy.  Your email/internet policy should clearly state (among other things) that:

  • the employer has the right to monitor employees’ use of email/internet; and
  • there is no expectation of privacy in their use of email or internet at work. 

Here is sample language for your policy:

For business and legal reasons, the Company reserves the right to monitor the usage of its Electronic Communication Systems (the Company’s e-mail, internet, cell phones, fax machines, computers and networks) and to monitor and inspect any and all information received, contained or transmitted on its Electronic Communication Systems (including all related hardware and storage devices).  In exercising this right, the Company may, among other things, inspect files, data, or messages (including those that may appear to be deleted), electronically scan employees’ e-mail for information or activity that may violate this Policy, identify Internet sites viewed by employees, and view text messages sent on cell phones.  Where the Company deems it appropriate, it may disclose to third parties activities or information identified from monitoring or inspection.  Employees do not have any expectation of privacy in connection with their use of the Electronic Communication Systems, or with the transmission, receipt, or storage of information in connection with their usage of the Electronic Communication Systems. 

You also want to be able to prove the employee was notified of these rules and consented to them.  The best way to do this is with a signed acknowledgement.  While a generalized acknowledgement to the employee handbook will work, a specific acknowledgement identifying your email/internet policy is preferred.

Should you obtain written statements from witnesses?  In some situations it may not be feasible, but generally, yes, it is a good idea to have a signed statement from a key witness either proving or disproving the complaint.