Criminal Defense Investigation: Theory, Practice, and Methods

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Recommended citation:

Pennington, Jeremy. Criminal Defense Investigation: Theory, Practice, and Methods. Ironton: Pennington & Associates Ltd., 2016


Defining the Issue

Doing any type of investigation, the first goal must be defining the focus and breadth of the investigation. A criminal defense investigation is no different, and in this type of investigation, defining the fundamental issue or issues is undertaken both at the onset of the investigation and throughout the entire lifespan of the investigation.

Initial Criminal Defense Investigation Checklist

The onset of a criminal defense investigation can be overwhelming. For a novice perspective, an investigation may seem to be a straightforward process: the defendant is accused of a crime, the criminal defense investigator completes tasks A through Z, and the results are communicated to the responsible attorney. However, in reality, this the process is not that simple. Each defense investigation is unique and has special issues and needs that the criminal defense investigator must resolve and meet.

The initial stage of a criminal defense investigation is critical. Many investigations will require an A through Z approach. However, many others will result in a somewhat limited approach. In simple terms, the criminal defense investigator will be required to resolve only a specific issue. For example, some investigations will only consist of interviewing a witness, while others will entail a large, complex set of investigative operations. The key is to determine the specific needs of the investigation before any investigative task is undertaken. After determining the specific needs, a specific investigative strategy can be developed.

Typically, a criminal defense investigation will be prompted and initiated by the responsible criminal defense attorney by retaining the services of the criminal defense investigator. However, in some cases, the defendant or the defendant's family will retain the criminal defense investigator’ services. In the author's experience, requests for an investigation at the initial trial level are typically prompted by the responsible attorney, and most post-trial criminal defense investigations are prompted by the defendant. As a result, the initial intake process of a new criminal defense investigation can vary widely depending on who has prompted the investigation. Thus, the investigator needs an efficient means of meeting these requests that will enable a successful resolution.

The criminal defense investigator has an absolute need for an efficient and diagnostic approach when accepting new cases. This is not a matter of communication, business process, or legal agreement, but one of determining the specific needs of each case. The criminal defense investigator should utilize a structured checklist as part of the initial intake process when accepting a new case.

The checklist should include the following questions, which should be addressed explicitly by the criminal defense investigator:

  • What criminal allegation prompted the need for a criminal defense investigation?
  • Is the criminal defense investigator appropriately licensed to investigate the allegation? Is there a possibility that the investigation will require additional licensing?
  • What are the key defense questions that needs to be answered?
  • How can a criminal defense investigation make a unique and meaningful contribution?
  • Have the key defense questions or similar questions already been answered by the criminal defense investigator or law enforcement?
  • Who are the principle consumers of the criminal defense investigation? Will their needs be addressed through the criminal defense investigation?
  • What are the possible answers to the key defense questions? What alternative explanations should be considered before making a determination?
  • Would the criminal defense investigation benefit from structured analysis techniques?
  • What potential sources of information would be beneficial in answering the defense’s questions? Are the sources available?
  • Where should the criminal defense investigator seek assistance, information, or expertise during the investigation?
  • Should a brainstorming session be utilized to identify key assumptions, alternative criminal theories, or potential drivers of the criminal allegation?
  • What is the best way to communicate the results of the investigation? Should parts of the results be represented through diagrams or charts?
The Initial Criminal Defense Investigation Checklist is a structured analysis technique. Each question should be independently, critically accessed before an investigation is initiated. In turn, key points are accessed. For example, the checklist forces the criminal defense investigator to assess possible source of information. In the case of a crime that allegedly occurred twenty years prior, information sources will be a significant issue. The investigator will have to critically assess the availability of information and may even reject the case on this basis, depending on the needs of the investigation. Thus, the Initial Criminal Defense Investigation Checklist is a critical assessment of the proposed investigation and the likely issues that the criminal defense investigator will face if they choose to proceed.

The initial stages of a criminal defense investigation are largely a routine process. The same type of information is requested from the criminal defense attorney in all cases. This information could be viewed as foundation information. Without this information, no real actionable utility can be realized. However, the criminal defense investigator must realize this is only a starting point and the ensuing search for information is never routine. Once the foundation information is received, the actual investigation begins.
During any criminal defense investigation the following information should be collected.

  • All law enforcement reporting
  • All known witnesses' information
  • All witness statements
  • All photographs, video footage, and diagrams
  • All lab reporting
  • All evidence handling documentation
  • Information identifying all involved law enforcement officers and support personnel
  • Law enforcement and support personnel training and personnel records, including CVs
  • Appropriate law enforcement agency policy and procedures
  • Any reporting prepared by a non-law enforcement agency and information on involved personnel
As a matter of course, most of the above information should be contained in the discovery file. If it is not, the criminal defense investigator should recommend the information be requested through discovery in a written memorandum to the criminal defense attorney.

Defining Issues During an Investigation

The goals of a criminal defense investigation are often abstract? Simply stated, if the goals were clear, there would be no need for a complete investigation and the endeavor would be reduced to a collection operation only. For example, a goal of an investigation could be to identify the murderer who killed Jane Doe. However, this is not really a goal but rather an agenda encompassing an array of investigative issues that have no real foreseeable end or solution. Issue definition is an abstract endeavor at the micro level of any investigation. Once the investigation is underway, at times, defining an issue can seem difficult at first glance. However, defining each issue faced during an investigation is critical for that investigation to be successful.

If each issue is not defined, a haphazard approach results. In general, any criminal defense investigation is not comprised of just one issue but an array of issues. For example, a witness provides testimony based upon their personal observations of an alleged assault. What issues could exist with this testimony? For example, is the witness credible? Several possible issues could be defined in relation to this witness testimony or any other witness testimony. The goal is a break down the issue into subparts that can be explored through a collection operation and then assessed through analysis.

Where does an “issue” arrive from during a criminal defense investigation? An “issue” is an investigative question that emerges when an information gap is identified. For example, how did the alleged victim arrive at the alleged crime scene? This is an investigative question that requires a specific set of issues to be defined in direct relation to the question. Over the lifespan of a criminal defense investigation, a diverse array of investigative questions will be posed and answered. Initially, these investigative questions will emerge while building a model of the alleged crime. Then, more investigative questions will emerge during the assessment of the hypotheses. The model and hypotheses require information so that they can be assessed.

The following nine-step process should be utilized when attempting to answer an investigative question:

  • What is the defense’s question that needs to be answered?
  • Has the defense’s question (or similar questions) already been answered by the criminal defense investigator or law enforcement?
  • What are the possible answers to the defense’s questions? What alternative explanations should be considered before making a determination?
  • Would the defense’s question benefit from structured analysis techniques?
  • What potential sources of information would be beneficial in answering the defense’s questions? Are the sources available?
  • Should the criminal defense investigator seek assistance, information, or expertise while answering the defense’s question?
  • Should a brainstorming session be utilized to identify key assumptions?