Becoming a Homicide Detective

Introduction

Every day, law enforcement agencies across the United States receive reports of suspicious deaths. The agencies are then forced to dispatch officials who are mandated with the responsibility of investigating the deaths. Homicide detectives are among the officials who join other agents in unearthing the cause of a suspicious death (Snow, 2005). There are a number of tools and techniques that homicide detectives rely on in their quest to understand how an individual died. The detective may examine the body for any signs of harm inflicted by the self or some other party. Defense wounds and wounds resulting from the use of blunt force are other signs that offer insights into the cause of death (Snow, 2005). This paper explores the duty of a homicide detective. It examines some of the procedures and methods that homicide detectives employ as they execute their mandate.

Background

It has already been mentioned above that there are different methods and procedures that homicide detectives use when trying to determine how a death occurred. The procedures and methods that are used are determined largely by the circumstances surrounding a death. For example, if initial investigation reveals that hanging was the cause of death, the detective employs relevant techniques and procedures. While this remains true, it is important to recognize that there are certain procedures that feature in nearly all investigations of death. For example, it is common practice for detectives to examine the body for any signs of use of blunt force or attempts by the victim to defend themselves (Geberth, 2016). Establishing the time of death and determining the factor responsible for the death are some of the initial tasks that a homicide detective handles. These tasks allow the detective to identify and rule out suspects. In the following section, a discussion of the common procedures that detectives use is provided.

Establishing the time of death 

One of the first tasks that homicide detectives perform upon arriving at the scene is establishing the time when death occurred. It is important to do this for a number of reasons. One of these reasons is that by establishing the time of death, the detective is able to narrow down on the possible causes of death (Hess, Orthmann & Cho, 2016). The other reason is that the detective is able to begin identifying suspects. For example, when a suspect provides an alibi, determining the time of death allows the detective to verify and confirm the alibi. In the discussion that follows, some of the common factors that aid in the determination of the time of death are explored in detail.

Algor mortis

Upon death, the human body undergoes decay that occurs in a number of phases and involves various chemical and physical changes. These changes allow for the time of death to be established. Algor mortis is one of the changes that the body undergoes post-mortem. Essentially, Algor mortis involves temperature changes. The temperature of a human who is still alive remains fairly constant. This changes when death occurs. Upon death, the body’s temperature declines and this fall in temperature continues until it (the body temperature) matches the ambient temperature (Hau et al., 2014). During the first hour after death, the decline in body temperate is insignificant. This decline becomes more noticeable in the succeeding hours. The decline occurs at a steady rate and this allows for the time of death to be established. However, it is important to note that Algor mortis does not offer an accurate indication of when the death occurred. This is because there are numerous other factors that determine the rate of temperature decrease. Furthermore, Algor mortis becomes unhelpful when the body has been dead for too long. For this reason, detectives should begin their investigation as soon as possible and Algor mortis should be combined with other factors to arrive at an accurate time of death.

Rigor mortis

Rigor mortis is another process that enables homicide detectives to understand when a death occurred. This process kicks off 1-3 hours after death has occurred. It is characterized by the freezing (stiffening) of the joints (“Rigor Mortis”, n.d). Both voluntary and involuntary muscles are involved in this process. Cutis anserine is a characteristic feature of this process. Essentially, the appearance of “goosebumps” indicates that a body is in this stage of decay (Hau et al., 2014). Rigor mortis occurs when the cells of the body are robbed of their capacity to eliminate Calcium and this results in a buildup of this element in the cells. The buildup forces muscle fibers to become linked, thus leading to stiffness. Rigor mortis can provide detectives with insights that allow them to establish the time of death. The process can last for up to 24 hours after death occurred. Therefore, if a detective observes that the body is still stiff, they may conclude that death occurred within the last 24 hours.

Livor mortis 

The third process that the body undergoes post-mortem is livor mortis. This process is characterized by discoloration. This process is initiated when the heart beats no longer and the lungs stop performing their function. As these organs fail, cells no longer receive oxygen and blood. The discoloration is observed on the upper sections of the body as blood moves to the lower section. While the upper sections of the body become paler, the lower sections acquire a darker color. It is important to note that gravity also plays a role in causing the blood to move to the lower sections of the body (Hau et al., 2014). Livor mortis begins almost immediately after death (20-30 minutes) after death and reaches its peak after 12 hours (“Stage 4”, n.d). This timeline can be used by the homicide detective to establish when death occurred.

Decomposition

Decomposition is yet another process that the body undergoes post-mortem. It takes only four minutes for the decomposition process to begin (Vass, 2001). However, during the first two days, it is nearly impossible to understand that the body has began decomposing by merely observing it. Most of the changes that occur in this period are internal. From the second day, some external changes can be seen (“Decomposition”, n.d). For instance, the body becomes bloated as bacteria release gases that become trapped in the abdomen. Such parts as the eyes and the tongue become bloated and a change in the color of the skin may also be observed (“Decomposition”, n.d). From the fifth day after death, proper decay begins. The body emits strong and foul odors as gases are released. As the flesh decomposes, the body enters a post-decay phase. This phase occurs 10-24 days after death (“Decomposition”, n.d). Decomposition continues until the body is stripped of all flesh and bones are all that remain. The different phases of decomposition provide the homicide detective with insights that can be used to identify the time of death. It should be noted that such factors as the environment and the temperature affect the rate at which the body decomposes (Mann, Bass & Meadows, 1990). If the body is in a hot environment where insects can colonize it, the rate of decay will be faster than when the body is in a cold environment. Such factors as performing an autopsy on a body do not seem to have any significant impact on the rate of decomposition (Bates & Wescott, 2016). The homicide detective must consider these factors when seeking to determine the time of death.

Determining the cause of death

With the time of death determined, the homicide detective can then proceed to establish what caused the death. The cause of death can be established by examining the wounds on the body. The nature of the wound can allow the detective to determine if any weapons were used. The detective should also keep an eye out for any indications of suicide or defense. In the following discussion, some of the factors that guide the determination of the cause of death are examined.

Wound patterns

As already mentioned above, by examining the wounds on a body, the detective can determine what caused the death. The patterns of the wounds can particularly enable the detective to identify the type of weapon that was used. Research indicates that the thorax is the part of the body that is targeted when sharp force is used (Ambade & Godbole, 2006). On the other hand, the head is mostly targeted by those who employ blunt force. By identifying the location of the wound, the detective should be able to determine the weapon that was used. For instance, if the wound are on the head, the detective may conclude that blunt force was used (Ambade & Godbole, 2006). Defense wounds also allow the detective to determine the cause of death. When blunt force is used, defense wounds are usually found on the forearm while the wounds appear on the hands when sharp force is employed (Ambade & Godbole, 2006). The wound patterns also offer insights that can guide the detective in determining the weapon that was used. In most cases where blunt force was used, the perpetrator use iron or wooden rods. On the other hand, knives are the preferred weapon for perpetrators who employ sharp force (Ambade & Godbole, 2006).

Gunshot wounds

Gunshot wounds are rather common in the United States. Figures indicate that each year, as many as 250,000 cases of these wounds are handled by medical practitioners (“Evaluation of Gunshot”, n.d). While many of those who develop these wounds survive, there are some who succumb. It is the mandate of the homicide detective to determine if an individual died from gunshot wounds. The pattern of the gunshot wound can be used to identify the type of gun that was used. For example, the entrance holes tend to be single and punched out when close range weapons are used (Breitenecker, 1969). The nature of the wounds sustained by internal organs is also determined by the distance from which the shot was fired. Close range shots tend to destroy target organs completely while the organs scatter in pellets when the shots are fired from a distance. The presence of exit wounds also serves as a guide for determining the type of gun used. When the wounds are present, it means that the shot was fired tangentially (Breitenecker, 1969). This determination enables the detective to zero in on the suspect. The trauma that the body exhibits can also offer indications of the cause of death. In most cases involving gunshot wounds, only one form of trauma is observed (Betz & Eisenmenger, 1997). In addition to offering insights on the type of weapon used, gunshot wounds can also provide more specific clues. For example, detectives can examine the bullet wound to determine such issues as the type of bullet and the speed at which it was travelling (Hollerman et al., 1990). The detective should combine all the insights in this discussion to determine that a gunshot caused the death and to rule out all other possible causes of death.

Homicidal and suicidal deaths 

Dyadic deaths are rather uncommon but some cases have been reported. Essentially, these deaths involve homicide and suicide (Kuchewar & Bhosle, 2015). They occur when the perpetrator commits suicide after murdering another person. Homicide detectives are needed to determine the cause of death in these situations. There are various insights that the detectives can rely on to identify suspects and to determine with certainty that the death is homicidal or the result of suicide. In cases where strangulation was involved, the nature of injuries can be used to determine what caused the death. The victims show little signs of self-defense as defense wounds are usually lacking in most murders involving strangulation (Harm & Rajs, 1981). Fractures on the larynx can also serve as evidence that strangulation was responsible for the death.

Identifying suspects 

The ultimate objective that homicide detectives pursue is the delivery of justice. Identifying the suspects behind homicides is one of the aims that allow them to achieve this objective. There are various measures that the detectives can institute to identify the suspects. These measures are situation-specific and wisdom is needed when determining the measures to implement. There are a number of issues that the detective can turn to as they seek to determine the suspect. Some of these issues are examined in the discussion below.

Mental health of suspects 

In an earlier discussion, dyadic deaths have been highlighted. While they remain rare, these deaths are intriguing and provide lessons for homicide detectives and other law enforcement agents. One of the issues that can be determined from an investigation of this type of death is the mental state of the perpetrator. It has been noted that in most cases of dyadic deaths, the perpetrator was mentally ill. (Lew, 1988). The mental illness can receive blame for the actions of the perpetrator. There have been cases where the perpetrators murder close family members before committing suicide (Lew, 1988). These cases highlight the tragic nature of dyadic deaths.

Relationship to victim 

Apart from revealing the mental state of the perpetrator, investigations can also offer insights into the relationship between the victim and the perpetrator. An investigation conducted by Teet Harm and Jovan Rajs revealed that the perpetrators of strangulation that result in death were closely related to the victims. They noted that 60% of the murders are committed by close friends and members of the victims’ families (Harm & Rajs, 1981). Sexual partners are also suspected of being behind murders in which the victims were first sexually assaulted before being killed. In an earlier discussion, it was noted that the nature of wounds can reveal if the force used was blunt or sharp. These wounds can also allow detectives to identify the possible perpetrator. It is understood that when the perpetrator is known to the victim, blunt force is more likely to be used (Ambade & Godbole, 2006). On the other hand, criminals who are not related to the victim tend to use sharp force. Detectives can use therefore rely on the nature of the wounds to determine if the perpetrator was a close family member or some stranger.

The efforts by the detective to identify the suspect need not be limited to the nature of wounds and an investigation of the relationship to the victim. There are other tools that detectives can rely on. For example, eye witness testimonies are reliable resources for identifying suspects. Forensic investigations involving such techniques as DNA analysis can also allow detectives to identify suspects (Swanson et al., 2012). The homicide detective should employ all available tools and techniques to ensure that the suspect is identified and that justice is delivered.

Conclusion

Homicide remains one of the major causes of death in the United States and across the globe. The criminal justice system is committed to protecting communities and ensuring that victims are provided with justice. Homicide detectives play a vital role in enabling the criminal justice system to execute its mandate. As they perform their duties, there are a number of tools and procedures that the detectives rely on. Establishing when a death occurred and the cause of the death are among the tasks that the detectives perform. Various insights allow the detectives to perform these tasks. The successful execution of these tasks enables the detective to promote justice and ensure that perpetrators do not get away with crime.

References

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