Witness interviews are a source of information when investigating an allegation.  Interviews are usually conducted after document review has been completed.  Potential interview subjects include not just current employees, but also former employees or third parties, depending on the sensitivity of the investigation.

At the outset of an interview of a company employee, counsel for the company should administer an Upjohn warning to protect the attorney-client privilege and work-product doctrine, and to avoid any confusion on the part of the witness regarding the role of counsel.  An Upjohn warning explains to the witness that company counsel does not represent the witness, that the discussion is privileged, that the privilege belongs to the company, and that the company may, in its discretion, waive the privilege.¹ 

If the interview is taking place outside of the United States, care should be paid to any local confidentiality or privilege rules.  In the UK, for example, privilege will not necessarily apply to the records of a conversation between a lawyer conducting an investigation and a company employee from whom the investigator is seeking information, regardless of whether or not an Upjohn warning is provided.