An estimated 1,197,704 violent crimes occurred nationwide in 2015 according to the Federal Bureau of Investigation's Uniform Crime Reporting Program. Violent crimes are determined according to a Hierarchy Rule: Murder, Non-Negligent Manslaughter, Rape, Robbery, and Aggravated Assault. The collection, preservation, and forensic analysis of the evidence with most crimes are often critical in determining a person's guilt or a person's innocence. The forensic exam is beneficial to Law Enforcement, and the medical setting to provide a comprehensive medical forensic examination with the collection of evidence knowing the patient's body is the crime scene. Evidence must be identified, collected, packaged, secured, and maintained correctly, then released to Law Enforcement following a strict chain of custody rules so that it can be analyzed appropriately and used later in legal proceedings. When collecting evidence, the examiner must wear gloves at all times and change them often utilizing the clean technique. Following proper collection, handling, and storage of evidence will reduce the possibility of cross-contamination or degradation of DNA.[1][2]
Trace Evidence
May consist of debris such as dirt, soil, sand, gravel, grass, leaves, twigs, adhesives and tape, fibers, glass, or bullet fragments.
When trace evidence is identified the following steps in the collection of the evidence is outlined below:
Biological Evidence
May consist of blood, skin, hair, semen, saliva, and urine.
The same process for packaging, securing, and maintaining the evidence as outlined above is used for the collection of trace evidence.[4][5]
Clothing Evidence
Clothing that is worn by an individual at the time of the crime often contains physical or biological evidence that must be preserved. If the patient is wearing the clothes they had on during the assault, all items can be considered evidence. If the patient is not wearing the clothes they had on during the assault, clean clothing put on later by the patient such as underpants in the case of a sexual assault may still contain bodily fluids other than the patients. The patient's clothing must be handled and examined carefully to avoid loss of evidence. Each piece of clothing must be dried thoroughly if wet or damp. Each piece must be identified, labeled with the patient's identifying information, date, time, and initials of the examiner. All stains or tears to the clothing must be documented. When these steps have been completed, each piece of clothing must be placed in separate bags to avoid cross-contamination. The clothing placed in the individual bags must be identified, labeled with the patient's identifying information, the examiner's signature, initials, date, and time. Each bag is then placed in a larger bag which is properly labeled with the patient's identifying information, the examiner's signature, initials, date, and time. When clothing is collected it must be correctly identified, packaged, preserved, secured, and maintained until released to law enforcement with the proper chain of custody for further analysis at a forensic/crime laboratory.[6]
Injury to the Body
The forensic examiner will take a history from the patient to help guide in performing a detailed head to toe assessment to identify injury or findings to the patient's body. Injury or findings must be documented by taking photographs, measuring the injury utilizing measuring tools and/or using age-specific body diagrams. It is very important that the correct terminology is used to describe injury and findings. For example, medical personnel confuses lacerations versus cuts. Lacerations are caused by blunt force trauma, and cuts are caused by sharp force trauma usually by a sharp object.
It is critical to correctly identify the injury and the mechanism of the injury:
Again to emphasize, when possible the examiner may use a camera, measuring tools, and age-appropriate body diagrams to document the medical forensic examination.
Keeping the Evidence Secure[7]
Collection, preservation, and securing evidence is critical from the time it is collected. Completion of chain of custody documentation is also critical. The chain of custody form must contain information about the evidence collected and must remain with the evidence until it is released to law enforcement. The patient's identifying information with the date, time, Law Enforcement involved with the case number must be included. Each person who has had contact or possession of a piece of evidence must be identified on the chain of custody form from the time it is collected and then released to Law Enforcement. If the chain of custody documentation is incomplete, inaccurate or omitted it will cause the evidence to be inadmissible in a court of law.
Important factors to follow when collecting evidence:[8][9]
Collect evidence correctly, preserve each specimen separately, use and change gloves often, avoid coughing or sneezing during the collection, use appropriate tools such as cotton-tipped applicators, sterile water, cardboard swab boxes, separate paper bags, and envelopes to prevent cross-contamination of samples collected.
Allow swabs to dry thoroughly, dry with cool air only, no heat, package in a vented swab container boxes or paper. Do not use plastic. All these steps will preserve the integrity of the samples collected.
To maintain accurate identification, each sample must be labeled with the patient's identifying information--patient's legal name, date of birth, medical record number, date, time, and the examiner's signature.
The forensic examiner must be knowledgeable about the medical forensic examination and the different types of evidence of why, when, where, and how to collect, preserve, maintain and release the evidence.
Many patients will present with needs for a medical forensic examination with collection of evidence. Many professionals will be involved in the care of these patients---physicians, nurses, advanced practice nurses, forensic nurse examiners and other healthcare providers. The healthcare provider should have advanced training in the care and overall assessment of the patient. Ongoing education and training is important due to the ever-changing advances in treatment and technology and can be achieved by attending conferences, reviewing published research studies and using current guidelines and recommendations. Each healthcare provider is an important member of the team to accomplish the best outcome for the patient and to assist with future follow up care and resources. Many patients will have law enforcement involved for investigative purposes and possible legal proceedings. The healthcare provider may be needed to testify in a court of law at a later date, usually years later. It is vital that a thorough examination is performed, documentation is completed and the evidence collected at the time of the examination are all complete, accurate, and concise.
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