Most of us have used a timeline either formally or informally to collate information obtained in an investigation. In simple cases, this can be done informally by simply mentally organizing relevant information into the correct order. For example, the deposit was placed in the safe after being counted by the manager and her assistant at 10 p.m. the previous day. The following morning, Mike and Jennifer entered together at 9 a.m. and prepared to open the store. The safe was opened at 9:15 a.m., so the registers could be prepared. The store manager arrived at 10 a.m. and discovered the deposit missing from the safe.
This simple timeline broadly organizes the details that may be relevant to the investigation. This organization of details allows the investigator to assess the available facts and begin to see where further inquiry is needed. Clearly, this sort of timeline has many gaps that need to be filled to discover even the scope of possible individuals involved. In more complex cases, the details may be plotted on a physical timeline, so they can be visually represented and added to as information becomes available. This visual representation of events often points investigators to areas that need inquiry or that contradict alibis. With complex bribery or fraud cases, being able to see the relationship between meetings, orders, or personal purchases can help you understand the fraud. The timeline can also be important when updating superiors on the case progress, so they can quickly see how the investigation is developing.
The Timeline Interview
There’s another use for a timeline that is different than simply listing when the events occurred and people who were present. Allowing a witness to use a physical timeline as they recall the event helps them organize information, actions, and descriptions. Importantly, the timeline interview is compatible with the cognitive interview.
The cognitive interview was developed by Professors Fisher and Geiselman to assist in the recovery of memories from victims and witnesses. This interview increases the accuracy and amount of details from the subject while reducing suggestibility. More recently, the cognitive interview for suspects has been validated as an investigative tool to help identify individuals involved in incidents. The research into the cognitive interview for suspects indicated investigators were able to accurately identify deceptive individuals between 85 and 100 percent of the time.
The cognitive interview and the cognitive interview for suspects both begin with instructions that put the subject back into the context of the event that they witnessed. The witness is asked to report everything—see what they saw, hear what they heard, and feel what they felt at the time of the event. By beginning the memory retrieval shortly before the event occurred, it allows the individual to place themselves back into their memory, experiencing the observation in the same mental state in which they first observed it. This mnemonic, or memory trick, helps the individual recall more information more accurately. The subject then begins their narrative recalling details of the event that they observed.
The timeline technique is compatible with the cognitive interview using similar instructions to begin the process. Especially effective with multiple people involved in the incident, the timeline allows the witness to create a sequence of events before the actual interview with the investigator takes place. We first learned of this technique at an interviewing conference in Norway last year with Professor Lorraine Hope, the timeline study’s author. During the two-day master class, we had several opportunities to explore its utility retrieving old and newer memories.
Retrieving a memory is not a linear process. When a memory is first retrieved, it is done in zigs and zags. Pieces of the memory first reported jog other components of memory to retrieve additional details and so on until the narrative is complete. After several tellings, the “story” becomes more of a start to finish narrative. In most people’s memory retrieval, they first focus on the “highlights” of the event and then add additional details that are associated with them. In the first research of this idea by Hope in 2013, the timeline technique elicited more accurate information than just free recall without impacting accuracy of the details.
The timeline technique has the investigator provide the witness with a physical timeline. This physical timeline is a piece of paper or cardboard about twelve by thirty-six inches with a line drawn from the midpoint on the left side to the midpoint on the right side. This line represents the time of the observation from its beginning until its end. The witness is provided two different colored Post-it Note pads, one representing individuals in the event and the other color for the details or actions that occurred.
The witness is then instructed to use the color representing individuals to write what they remember about identifying features of each person observed and place them above the timeline where they were first observed. If they are able, they may include the person’s name if they know it or just uniquely identify them if the identity is unknown, such as “subject 1” or “red shirt.” Any later memories related to descriptions of the person should be added to that Post-it Note above the timeline.
The other color is used to write descriptions of any details, conversations, or actions they observed. The witness is told that these Post-it Notes should be placed below the timeline in the order they occurred during the event. Again, if additional details are recalled, they can be written on the original sticky note, or another note can be posted to it.
Once the individual has been instructed about the timeline’s use and the reinstatement of the events context has been reviewed, the person is asked to write down six or as many things as possible before beginning to retrieve their memories of the incident. The investigator should be available but does not participate in prompting or asking questions. Their presence is simply to answer any questions the person might have concerning the use of the timeline. Since the investigator is just sitting with the subject and not participating in developing the timeline, they may want to bring something to work on or read while the witness works to retrieve the memory.
It is useful for the investigator to observe the witness as they work to reconstruct the details. In our limited experience using the timeline interview, people seemed focused on the task and were actively working to recall information in the sequence making detailed notes on the Post-it pads. Since truthful people provide more details about an incident, someone who does not appear to be working to recall information should give the investigator pause.
There may be instances where an individual needs help writing because of penmanship or literacy, which may require the investigator to assist in filling out the Post-it Notes. The investigator should give the same instructions and ask the person to name six things they remember about the incident. The investigator then puts each on a separate Post-it Note and asks the witness to place it in the proper sequence on the timeline. Using the first recalled detail, the witness is asked to expand with additional information, which is written on the sticky note. This may prompt a new topic, which should be added to the timeline on another sticky note for the witness to place in the proper location.
The investigator waits quietly while the witness finishes writing on the Post-its and placing them on the timeline in their appropriate locations. Once the witness has indicated that they have gone as far as they can in the retrieval process, the investigator can take the timeline for a review. This will give an overview of the witness’s information, providing a context for each event or conversation. The investigator can now assess where additional probing will be required or identify areas that seem to have been omitted.
As the investigator reviews the timeline, they can begin to plan the organization of the following cognitive interview. It is probably useful to restate the instructions given prior to the timeline interview. Again, the investigator instructs the witness to go back into their memory seeing what they saw, hearing what they heard, and feeling what they felt at the time of each component of the memory. They are asked to report everything that they can remember, even if it might not seem useful. Now, the investigator begins to expand the memory using open-ended questions in the cognitive interview.
The timeline interview is useful in situations where there are multiple individuals, locations, or conversations that must be investigated. The most typical type of investigations where this would be used might be a sexual harassment investigation where there have been multiple instances or conversations that must be documented. This also might be useful in an organized retail crime investigation where one is debriefing an informant or cooperating suspect. Having an untainted narrative and timeline before beginning the actual interview with the subject will help the investigator in asking appropriate questions while avoiding contamination of the interview.