A good investigation interview is only as good as the person conducting it. If the investigator is aggressive, cold, accusatory, or unprofessional, the subject will feel uncomfortable and likely shut down. On the other hand, building good rapport and communicating person-to-person with the subject can help you gather the details you need to conclude a case.

As with all skills, practice makes perfect, but there’s no harm getting a bit of help along the way. The most effective interview techniques involve good preparation, asking the right questions, staying objective, developing details, and summarizing the information you've gathered.

Wondering how to conduct an effective investigation? Follow these 40 interview tips to get the most out of your interview subjects and to determine what questions to ask in the investigation interview.

Preparation

A major part of conducting a good subject interview starts long before the date of your meeting. Investigators should choose a time and place to meet that makes both them and the interviewee feel comfortable. You should also ensure you have a plan of questions to ask, how to respond to the subject's questions for you, and an investigation timeline to share.

1. Pick a non-threatening place for the interview, such as a conference room or private office.
2. Give the interviewee a choice of times for the interview, being respectful of his or her workload.
3. Provide the subject with a rough estimate of the amount of time the interview will take.
4. Remove extra distractions, such as computers, files, paperwork, in the interview room.
5. Provide the interviewee with a comfortable chair that doesn’t face a window.
6. Create a comprehensive list of investigation interview questions that you can choose from, depending on the direction the interview takes.
7. Decide whether or not to record the investigation interview.
8. Put the subject at ease when he or she arrives and offer a glass of water or coffee.

Need more question ideas or tips on conducting an investigation at work? Download the free cheat sheet: Top 20 Questions to Ask in an Investigation Interview.

Questions

Not asking the right questions for the investigation can cause you to miss key details of the incident. Pose questions that will gather the information you need without leading, confusing, or accusing the interviewee.

1. Begin by establishing a baseline by asking simple, easy-to-answer questions that the subject is likely to answer truthfully, such as: How long have you worked at the company?
2. Ask open-ended questions to get the subject to talk, such as: "Tell me about…"
3. Avoid loaded questions, such as: Are you a tough supervisor?
4. Avoid questions at the beginning that can be answered with a yes or no.
5. Do not ask accusatory questions that indicate you think the subject is guilty.
6. Ask simple questions that address one fact at a time, rather than combining more than one idea into the same question.
7. Do not ask leading questions that prompt for the answer you want, such as: "Isn’t it true that you punched Jean?"
8. Ask yes or no questions at the end of the interview to pin down specific facts that were revealed during the interview.

Ready to get started?  Make it easy with your free PEACE Method of Investigative Interviewing cheat sheet.

Objectivity

Bias in investigations causes problems for everyone involved. It can cloud an investigator's judgement and keep them from reaching the truth of what occurred. It can also lead to wrongful discipline for the accused, which in turn can lead to a lawsuit for the organization. Remain objective, focusing on the facts you gather, not what you think happened.

1. Explain that you are taking every allegation seriously and are committed to finding the truth.
2. Ask the subject to keep the interview confidential only if you have already established grounds for confidentiality.
3. Don’t promise confidentiality, but tell the subject that you will share information with only those who need to know.
4. Avoid being too familiar or taking on the role of “one of the guys”.
5. Do not share information about what other interview subjects have said (unless you are interviewing the accused or trying to obtain information from a hostile witness).
6. Avoid expressing your thoughts, opinions or conclusions about the case or what the interviewee says.
7. Do not make agreements or deals with the subject.
8. Practice self-awareness by identifying your own potential biases and putting them aside while conducting the interview.
9. Do not ask accusatory questions (i.e., "Why did you harass Linda?"). Instead, ask the subject to recall their version of the situation that happened on a certain date.

Development: Interrogation Questions

Once you've asked your initial questions, go back through and ask the subject for more details where needed. You can also use body language, supporting documents, and media files to help you develop the information you've been given.

1. If the interview is about a specific event, identify the five Ws: who, what, when, where, why.
2. Proceed in chronological order to ensure nothing is missed.
3. Ask about witnesses or others who can corroborate or comment on the incident.
4. Ask the subject to recreate the dialogue of the incident, in order of what was said.
5. Request any notes, documents, phone messages, or other evidence.
6. Identify the source of the subject’s knowledge: hearsay, rumor, eye witness, other direct knowledge
7. Take detailed notes (or have another person present who is taking detailed notes) that list only what is revealed in the interview, without opinion or comments.
8. Note the subject’s body language and physical movements, but without interpretation. For example, write that the subject was tapping his foot rapidly, but not that the subject seemed nervous.

Learn how to build trust and credibility with interview subjects with your free Cheat Sheet on Building Rapport.

Summary

Finally, finalize and summarize the subject's account of the incident with their help. While you can always interview them again, try to gather as much useful information as you can the first time while you have them cooperating, to speed up resolution.

1. Repeat any questionable or confusing information back to the subject to ensure you heard correctly.
2. Get the witness to confirm any areas where you may have misheard or misinterpreted information.
3. Ask for clarification and more detail on any vague points.
4. Ask follow-up questions to establish more facts in the chain of events, for example: If you were in the cafeteria at 1pm, how did your access card register an entry into the library at the same time?
5. If the subject gave evasive answers or avoided a question, rephrase the question and ask it again.
6. Ask the subject whether there are any other questions they feel you should have asked or whether there is anything they would like to disclose before you conclude the interview.
7. Allow sufficient time for the subject to think before answering any final interrogation questions for suspects.
8. Use silence as a tool to prompt a reaction, when possible.