Practical Homicide Investigation®
The Preliminary Investigation at the Scene: The Detectives©

Article by Vernon J. Geberth, M.S., M.P.S.
Practical Homicide Investigation: Tactics, Procedures, and Forensic Techniques.
Law and Order Magazine, Volume 54, No 9 September, 2006
Article has been expanded for research.

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This article provides the homicide investigator/detective with flexible guidelines to follow in the preliminary investigation of death. The principles set forth herein have been excerpted from Practical Homicide Investigation® and are intended to help the detective and chief investigator at the homicide crime scene to systematically check and review all the facts applicable to the investigation.

Many times over the years I have heard the expression how "luck and chance" play a significant role in the successful conclusion of a case. However, I personally believe that "luck and chance are the residue of design and established protocol. The tactics, procedures and forensic techniques specified within this article are designed to elucidate the elements of good fortune.

I believe that the professional investigator creates his or her own "luck and chance" through the systematic application of basic time-proven and traditional investigative methodologies, which have been utilized by law enforcement agencies throughout the years, coupled with an appreciation for and an understanding of the advances in forensic science as well as its application to the investigative process.

Prior to leaving for the scene, the investigator should instruct the person notifying him or her that patrol officers at the scene should; preserve the crime scene, hold all witnesses and/or suspects ,avoid using telephones located within the crime scene, initiate a personnel log accounting for all activities at the scene, including identification of all persons who have had access to the scene and record the license numbers and vehicle information of all autos in the area of the crime scene (if applicable)

A murder or suspicious death necessitates an established protocol to assure the preservation of the scene and the integrity of the evidence, which will be gathered during the inquiry. In reality the First Officer initiates the investigation and the detective then assumes control of the case upon arrival at the scene. (See Law and Order "First Officer Duties" September 2005).

Preliminary Steps to be taken by Detectives Upon Arrival CHECKLIST

Upon arrival ascertain boundaries. DO NOT move blindly into an area and always confer before acting. Decide how to approach the scene considering paths of entry and exit. Make sure you have conferred with the First Officer or Detective. Perform the "Initial Survey" and remember to have the First Officer escort you. Use this opportunity to develop a mental image and "absorb the crime scene" Ascertain whether or not fragile evidence is present and assure collection of these items. Prior to any crime scene process, take "Work Photos" to limit scene intrusion. You can utilize a digital or Polaroid® camera.

In addition, the investigator should stop and observe the area as a whole, noting everything possible before entering the actual crime scene for the detailed examination. Only the investigator and detective supervisor should enter the homicide crime scene, of course, with the exception of the first officers, and even then only to confirm death and observe scene conditions.

Homicide investigators must be certain to record the time and place of events and any measurable evidence. It only takes a few moments of the investigator's time to record this information, which may prove vital to the investigation. Basically, there are three reasons for this emphasis on preliminary note taking. The question of time is frequently the first subject covered in a cross-examination. If the investigator cannot be sure of the time of events, he may lose credibility on the rest of the testimony. The subject of time may very well be the basis of an alibi. Note taking forces the investigator to slow down. It thereby sets a calmer tone for subsequent events at the scene, and also causes the investigator to pay attention to details in order to record them in the notebook.

Describing the Scene

A complete description of the dead body and the surrounding area, covering the following items, should be entered in the notebook of the investigator upon arrival. Although some of the points I have listed may seem quite obvious, I can assure you from my own experience that the obvious is sometimes overlooked, especially during this initial phase, as you attempt to "cover all the bases." Record the sex, appearance, age, build, color of hair of the deceased and a description of the deceased's clothing. Record any evidence of injury and apparent cause of death. Are the bloodstains wet or dry? What is the condition of the body (lividity, rigor, etc.)? Describe the color of the blood (bright red or brown). Note any tears in clothing and evidence of gunshot or stab wounds. Conduct a careful examination of the hands. Are there any wounds or a weapon? Note whether or not there is any jewelry (rings, watches, gold chains, etc.). If there is no jewelry, make a negative notation. The defense has been known to resort to dirty tactics during trials. If they can make you appear like a thief to discredit your testimony, they'll do it.

Describe the immediate surroundings as well as the position of body in relation to articles in the room. Note doors, windows, furniture, etc. If a weapon is nearby, take detailed notes. Do not handle it. Look for bullet holes or fired shells. Note: do not collect at this stage of the investigation. In poison and drug-overdose cases, note presence of drugs, bottles, or glasses.

Implementing Crime Scene Procedures

The first thing the investigator should do after confirming death is to take charge of the crime scene. In the absence of the detective supervisor, the homicide detective is responsible for the professional investigation, of which the preliminary investigation at the crime scene is the most important and sensitive aspect. When I instruct my classes I always remind the detectives in attendance to practice what I call "Crime Scene Etiquette." Basically, as a detective you are there to reinforce the First Officer's duties and assure Crime Scene Protection. Yet, at the same time you want to take charge in a manner that encourages cooperation and teamwork. A simple expression such as, "Hi I'm detective so and so and I assume you are the First Officer Could you please give me a quick briefing and then show me what we have and assure that I don't disturb anything?" Who could get mad or putout with that introduction? You have already acknowledged that the First Officer is in charge. You are about to assume responsibility for the investigation. You have deferred to the First Officer's official position and acknowledged that he or she has the most current information on the event and have indicated by stating, "Show me what we have," indicating that everyone present is working on the case.

At this point you are present to evaluate the entire crime scene and surrounding area. During this crucial preliminary assessment you rely on your personal experience to make adjustments accordingly. You may decide to expand the perimeter of the crime scene. You may decide to add additional scenes or you may cause the immediate collection of evidence.

Therefore, extreme care must be exercised to preserve and protect the scene, because even the smallest detail can suddenly assume vital importance in the case. Failure to implement proper crime scene techniques may irreparably damage the investigation. I have found that the best course of action is to treat each dead-body call like a criminal homicide until the facts prove differently.

If the crime scene is outdoors, a wide area surrounding the body should be cordoned off for later systematic examination. The patrol officers should be directed to isolate the body and secure the immediate surroundings from all persons.

If the crime scene is indoors, the job of securing the location is relatively easy to accomplish. It may be as simple as closing the door. The biggest problem is removing unauthorized persons from the scene. The investigation should begin with the walkway and front entrance to the structure. These areas and the location where the body lies should be considered part of the scene and appropriately secured.

The Teamwork Approach

The detective supervisor and homicide investigator are faced with a crime of the utmost gravity, one that is fraught with a complexity of possible motives and methods and a variety of physical evidence. Therefore, teamwork is required for a successful homicide investigation, and it is the detective supervisor and homicide investigators who must set the tone for this teamwork approach as they coordinate the different people involved in the responsibility of the inquiry into death, for example: the patrol service or uniform division, the detective division and other homicide detectives, the medical examiner or coroner, the crime scene technicians or fingerprint experts, the District Attorney, medical and ambulance personnel and other agencies such as the FBI if the homicide involves a federal employee.

Directing the Investigation at the Scene

Homicide investigators should attempt to obtain all pertinent information from the first officer - out of the hearing of any witnesses, the press, or the public - before taking charge of the investigation. As mentioned earlier, the detective should confirm the fact of death for himself. The investigator must also see that the duties of the first officer have been accomplished.

Preliminary Interview of the First Officer

The detective must ascertain that the scene is intact - that nothing has been added or removed since the arrival of the responding police. To determine this he goes directly to the first officer. A preliminary interview with the first officer can provide an up-to-date appraisal of the crime scene as well as an assessment of what has transpired since the discovery of the body.

The homicide investigators should obtain a detailed account of what the officer or officers have seen and done. Usually, the officers will offer an opinion as to cause, manner, and circumstances of death. Investigators should receive these opinions objectively and graciously. However, they should not allow themselves to be influenced prior to making their own observations. Often the first officers' opinions provide a valuable lead in the investigation. In keeping with the teamwork principle, give credit where credit is due. If a patrol officer's performance at the scene is outstanding or proves instrumental in solving the investigation, I personally recommend that an official report be forwarded to the officer's commander. This report should be initiated by the detective supervisor at the scene and sent through channels so that this officer will receive proper recognition.

When interviewing first officers, emphasis should be placed on their activities in the immediate area of the crime scene - for example, how they gained entry into the scene, the position of the body on arrival, things they may have touched or moved, condition of the doors and windows, odors, whether the lights were on or off, etc. It may prove valuable to have first officers document their activities and observations on official reports. In addition, I recommend that the investigator assigned to interview the first officers prepare an official report for review by the patrol officer to assure that it is correct, and then have the officer sign the investigator's report which will become part of the homicide investigation.

I have found that it is a good idea to keep the first officers at the scene to answer any questions about the appearance of certain objects when they arrived. In addition, they can report any observations of persons who were in the area when they arrived or who expressed some interest in the activities of the police.

Duties of the Detective Supervisor on Arrival at the Scene

The detective supervisor or chief investigator, upon arrival, will assume the responsibility for conducting the homicide investigation and will replace the initial investigator as the ranking officer in charge of the case.

It is extremely important that the detective supervisor and the homicide investigator not permit themselves to fall into a fixed routine. Previous experience is invaluable but can become a hindrance when allowance is not made for new possibilities.

Remember, each homicide case is distinct and unique and may require a fresh approach or perspective. Keep an open mind.

Practically speaking, no one at this stage of the investigation has all the answers, nor can anyone know for sure exactly what direction the case will take. However, the investigators should be guided by certain basic procedures at the scene.

Ascertain that there is an investigator at the scene, and that the crime scene is amply protected. Confer with the investigator and be brought up to date on the status of the investigation. Solicit any opinions or theories and objectively evaluate these with your independent observations. Determine any investigative needs and make assignments as necessary.

Confer with the ranking uniformed officer at the scene, and interview the first officer so that proper instructions can be given to responding investigators. Priority should be given to the removal of the suspect and/or witnesses to the police station. Each witness should be transported separately. However, before they are transported, the investigators at the scene should briefly interview the witnesses so that they may have the advantage of the witnesses' observations to guide their investigation at the scene. Written statements can be obtained later on at the police station and the information transmitted back to the detective supervisor at the scene.

Use an assignment sheet to indicate assignments as given. This sheet should contain he identification of officers assigned, the location of the assignment, the duties assigned, and the time the assignment was given. Later on it can be used as a control device to assure that official reports are obtained from the investigators assigned. In addition to fixing responsibility for certain investigative duties, the assignment sheet will eliminate duplication of effort as additional assignments are made and put on the sheet.

If a suitable communications center or command post has not been established by the patrol officers, the investigator or supervisor should take immediate steps to arrange for one. The station house, Communications Division, and the detective command should be apprised of the telephone numbers of the command post to facilitate rapid communication to and from the scene.

Designate an officer to keep a running timetable of events, including arrivals and departures at the scene. When the scene is released, the timetable should be turned over to the detective supervisor.

If the victim has been removed to the hospital, insure that proper action is being taken at the hospital regarding any dying declarations, clothing, evidence, etc.

It is advisable to have a detective contact the hospital and confer with the patrol officer and/or doctor. It may even be necessary to assign a detective to assist the officer in these procedures.

If the suspect has fled the scene, the investigator and detective supervisor must ascertain exactly what alarms have been transmitted, if any, and the exact information contained therein. Upon verification and the development of any new information, these alarms should be retransmitted.

Provide for the dissemination of information to all units involved in the homicide investigation. Ideally, all investigators should be aware of all aspects of the case. It is up to the detective supervisor to coordinate and disseminate this information to the "troops." Properly informed officers can better perform their own assigned functions and contribute more intelligently to the overall effort. This is especially true for those officers assigned to conduct canvasses. Uniformed officers assisting at the scene must also be made to feel that they are part of the team.

On occasion, too many officers respond to the homicide crime scene. The detective supervisor should not hesitate to direct these officers to return to their original assignments if they are not needed.


The homicide crime scene is, without a doubt, the most important crime scene a police officer or investigator will be called upon to respond to. Because of the nature of the crime, death by violence or unnatural causes, the answer to what happened can only be determined after a careful and intelligent examination of the scene. The preliminary investigation conducted at the scene by the detectives will provide for the intelligent and effective retrieval of evidence paramount to the successful conclusion and prosecution of the case.

"Remember, Do it right the first time. You only get one chance©."
Geberth, Law and Order 1980

Vernon J. Geberth, M.S., M.P.S., retired from the NYPD Homicide Division with the rank of Lieutenant Commander. He may be reached at These copyrighted materials have been excerpted with permission of the author from Practical Homicide Investigation: Tactics, Procedures, and Forensic Techniques. CRC Press, LLC. Article Has Been Expanded for Research.

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