CHAPTER 1
The Crime Scene
The best place to start is by defining what a crimescene is. A crime scene is simply any place acrime has occurred. It could be as small as asquare foot or less, or it can be large covering several placesin different areas or even different states. Most of the time,the crime scene is easily seen or defined. It is physical thingsthat can be seen by the naked eye or items that have beendisturbed or broken. It can be that things are physically notseen mainly because they are very small or missing. Then thereare the things that are there but can't be seen. Things such asfingerprints, DNA, hairs, fibers and chemical residues. Theseitems may require forensic processing. At times they can beprocessed at the scene. Some require processing at the crimelab or other locations. Crime scenes can be inside or outside ofbuildings. It can be a vehicle or just a single item. Every crimescene varies and is different. As different and varied as theyare they are all for the most part are processed in the samemanner. Some require more processing then others. Processesdiffer from item to item but the end result is always to achievethe same result, the truth of what happened. Crime sceneinvestigators follow a procedure that is the same for all scenes.Some of the steps may be eliminated from some scenes whilesome may be added to others depending on the items to beprocessed and the circumstances surrounding the scene. Aquick example would be why process for DNA if there are nobody fluids present? Why call the Medical Examiner if thereisn't a body present?
Let's examine a couple of typical crime scenes. I'll usethe word typical but there is no such thing as a typical crimescene. A better word would be a basic crime scene. We'llassume that you are our victim. You pull into the drivewayafter a long day of shopping and as you do you notice thatyour trash can has been moved and is under your kitchenwindow. The window is pushed up. You get out of your carand go to the front door and see that it is slightly open. Youpush the door open and look inside only to see that yourentire house is ransacked. You enter and see that cabinetsand drawers are opened. Your TV set and stereo equipmentis gone. During further examination of your home you findthat other items are gone. Your wife's jewelry is gone and soare your child's video games. You've been burglarized! Youcall the police. A patrolman arrives and takes a report. Youanswer dozens of questions. The officer then tells you that heis notifying the crime scene unit. He requests that you do notenter the residence until the crime scene unit arrives. It takes awhile but the crime scene unit arrives. The detective identifieshimself and again asks you several questions. These questionare more on the line of what's missing, the time you weregone and other question like "did you touch anything whenyou entered?"
The detective then begins his examination of the scene.He starts where the actor started, the kitchen window.The first thing he does is take photographs of the entirescene starting at the kitchen window and going through thehouse in the same order that the actor did. He takes overallphotographs of the scene as well as detailed photographs ofthe areas that were disturbed and of items the he determinesto be of value from an evidence stand point. These are theitems that he will process or collect to take to the crime labfor processing. Sometimes if the scene is large or extensive hemay take a video recording of the scene. The photographingand video recordings of the scene are necessary to preservea visual record of the scene. This and all the rest of what hedoes may someday have to go to court and be presented toa jury. Documentation is very important when it comes totrials and juries. Once the photographing and video recordingis completed the detective will start to process the scene forevidence. If the scene is large or difficult he may requestaddition detectives to assist him. He will decide at this pointwhich items he can process on scene and which items needto be taken back to the crime lab to be processed. When hefinishes he will determine what he will collect and bag theevidence that has to be taken to the crime lab. He will thenprocess the remaining items at the scene. He will probablystart dusting for latent fingerprints at the point of entry, thekitchen window. Before we continue let me explain the termlatent fingerprints. The word latent means that what youare looking for is not visible to the naked eye and has tobe developed to be seen. This is usually done with powdersbut there are other things that can be used as well such aschemicals, lighting angles while photographing and even usinglasers. If he develops a fingerprint he will collect it. This maybe accomplished by using lifting tape and placing the tapeon a card to preserve it. It may be that the surface that thefingerprint is on is not suitable for the use of lifting tape. Inthis case he may have to photograph the fingerprint usingvarious lighting methods. One of these lighting methods couldbe by the use of a laser or an alternate light source. Actuallylasers are not used that often anymore. A laser is basically avery bright light that operates in a specific light band and arevery expensive. Alternate light sources are bright lights thatuse different colors to get to different light bands. It is muchcheaper to buy and operate an alternate light source, whilea laser only operates in one light range. The alternate lightsource operates in several different light bands. These lightbands for the most part work best with florescent powders.In laboratory processing these light sources are combined withsuperglue processing and dye staining to further enhance thedevelopment.
The detective will continue to process for latent fingerprintsthroughout the scene. The items he processes are done one at atime until he reaches the exit area, in this case the front door.In addition to the interior or the residence the detective willalso examine the exterior or the building. He will be lookingfor things of evidence outside the scene. Remember our trashcan under the kitchen window? He would want to process thetrash can as well. He would also look around the can on theground for possible footwear impressions. These would haveto be photographed as well and he might even take a castingof the footwear impression. Other areas of interest would bethe way the actor entered or exited the property. These areaswould also need to be photographed. When a large amount orlarge items are taken it may be hard to take them away all atonce and they may be hidden outside or somewhere close by.For this reason a search of the area may be needed.
When the detective completes his examination he will placethe evidence he has collected in his vehicle to be returned tothe crime lab. He will advise you of the items he has takenand explain that they will be returned to you when the crimelab is done with them. There may be some items, dependingon the circumstances, that may take a while to return to you.He will advise you that his report will be sent to the detectiveassigned to investigate the case. If he has developed anyfingerprints in your home he will also take the fingerprints ofall the residents so as to be able to eliminate their fingerprintsfrom his findings. After all you live there, your fingerprintsare supposed to be there. By this time the detective assigned toinvestigating the case may or may not have contacted you. Ifhe hasn't he will and again you will be asked more questions.In a perfect situation where the actor is caught you will benotified. If the case goes to court you may or may not haveto testify at the trial in which case a prosecuting attorney willcontact you.
That is generally what happens in a basic crime scene.Now let's make things a bit different. You walk outside to getyour mail and notice a police car next door. Just about thesame time three more police cars arrive with lights flashingand sirens blaring. You see a police officer putting up yellowbarrier tape that says "CRIME SCENE—DO NOT CROSS".An officer approaches you and asks you if you have beenhome all day? You say yes and ask him what's happened. Hesays that there has been an incident next door but won't saywhat. He asked if you saw anything or anyone around thearea in the last day or so. You say no, you come to find outlater that a homicide has occurred next door. There are policeall over and the Crime Scene unit arrives. The detective talksto several officers and is taking notes as he speaks to them.Shortly thereafter several more Crime Scene units arriveand now there are several detectives on the scene. They areall involved in conversations and taking notes. They seem toseparate and go to their vehicles. They all start heading in thedirection of the house next door. They meet and talk. One ofthem places a large paper mat at the entrance to the houseand then they both put on paper shoe covers, coveralls andlatex gloves. They enter the house with the first police officeryou saw when you went out to get the mail. He also putson the shoe covers, coveralls and gloves. They spend severalminutes in the house. When they exit they take off the papershoe covers and rubber gloves and place them in a two largepaper bags. The patrolman returns to his patrol car and startswriting. The detective meets with the other detectives. At thispoint another detective puts on paper shoe covers, coverallsand rubber gloves and takes a video camera and a still camerainto the house with him. The others wait outside with casesof equipment. Two of the detectives seem to be examining theexterior of the house. They then take a video camera and a stillcamera and start to video and photograph the exterior of thehouse. A third detective is walking with them placing coloredflags on the ground in areas that are pointed out by the othertwo detectives. After about forty minutes the detective thatentered the house comes out and again places his paper shoecovers and gloves in the large paper bags. All the detectivesthen meet again and seem to be discussing something. Twomore detectives approach the house. They seem to be carryingwhat looks like a small canister type vacuum cleaner. Theyalso put on paper shoe covers and rubber gloves. You thenhear the vacuum start up. Well a lot has happened up to thispoint but what?
Let's go back to the beginning, the officer you saw outfront when you went to get the mail is what's known as thefirst responder. He was called to the scene when the postalcarrier noticed that the mail hadn't been taken out of the mailbox for three days. The officer responded to make a healthand welfare check. He found that the door was unlocked,entered and found the resident dead on the floor with whatappeared to be several gunshot wounds to the head and chest.He checked to house to see if there were any more victimsor if the actors were still in the house. He also observed thatthe house was in disarray as if someone was searching forsomething. He left the house careful not to touch anythingand called headquarters notifying them of the situation.Headquarters then sent the crime scene unit to his location.When the first unit arrived the detective talked to the firstresponding officer getting details of what he saw, the conditionof the scene when he entered and what he did inside. Whenthe other crime scene units arrived the first detective relayedto the other detectives the information he received from thefirst responding officer. They then decided who would dowhat aspects of the scene examination. The first detective onscene then went into the scene with the first responding officerto trace his steps as he went through the house. They put onshoe covers, coveralls and gloves so as to not contaminate thecrime scene with foreign substances from outside the scene.They also saved the shoe covers, coveralls and gloves to keepany trace evidence that they may have picked up inside thescene. A detective entered the house with a video camera andstill camera to document the scene as how it actually existedat the time of the detective's arrival. Again the shoe covers,coveralls and gloves were worn and saved to prevent crosscontamination. This detective has to be very precise in hisdocumentation of the scene with video and still photographs.Down the road as the investigation continues questions mayarise as to specific items which may help in the prosecutionof the case. An actor or suspect may have left or movedsomething that can tie him to the case and the video or stillscan substantiate these facts. The three detectives outside arelooking for items of evidence outside pertaining to the crime.This could be footwear impressions, cigarette butts, candywrappers, tire impression, etc. The entire exterior of the houseis also documented to see if there are any signs of forced entry.The officer with the flags is marking items that are found orthose things that appear to be relevant to the crime scene.When these tasks are completed the detectives will meet andrelay to each other their findings and completed tasks. Thetwo officers who enter the building with the vacuum cleanerare there to vacuum but not the way you think. Their purposeis to collect trace evidence. Trace evidence is smaller items ofevidence such as hairs and fibers. Part of the reason for theshoe covers and gloves is to keep trace from outside fromgoing into the scene and trace from inside going outside.This is known as the Locard's Principle. The principle wasdeveloped by Edmond Locard, a French forensic scientist. Hewas said to be the Sherlock Holmes of France. His principleis known as "Every contact leaves a trace." Locard's Principlesimply put is when you enter one area from another area youbring something from the area you came from into the areayou are going into. For the same reason when you are in acrime scene, you take evidence away from the crime scene tothe area you are going to. The detectives with the vacuum willvacuum all the areas in the crime scene including the victim'sbody. A different canister is used for each area. Each canisteris appropriately marked. When the detectives are done withthe vacuuming process detectives can enter the crime scenewithout shoe covers. Detectives will wear rubber gloves at alltimes while in the crime scene from start to finish so as notto leave fingerprints behind or damage fingerprints which arealready there that haven't as yet been developed.
Now the scene has been cleaned so the team can enterthe house. Once inside a multitude of things are starting tohappen. First is a scanning type search of each area is made.This is a preliminary search to locate obvious pieces ofevidence. These items are noted. Also at this point the MedicalExaminer is notified to examine the body. Upon his arrivalhe will examine the body for wounds and trauma aside fromthe obvious ones noted during the initial response. In mostcases he will give a time of death or try to establish one asclose as he can. A lot of factors can help determine the timeof death. Some of these items can be body temperature, roomtemperature, lividity, rigor mortis and decomposition. In mostcases when the Medical Examiner is done the body is removedfrom the scene and taken to the morgue to await autopsy. TheMedical Examiner will decide when the autopsy will be done.The body is then made ready for transport to the morgue.That means that the hands must be bagged to preserve anytrace evidence which may be present specifically under thefinger nails. The body is placed on a clean shroud (sheet) andthen placed in a clean body bag. The body bag is marked withthe name, date of birth, time of death of the deceased and thename of the physician who pronounce the victim dead. Thebag is then sealed by a detective who also signs and dates theseal. He also photographs the bag and seals. The victim's bodycan then be removed to the morgue.
The scene can then be processed much the same as it wasin our burglary scene before. There are a significant numberof other processes which have to be done in addition to whatwe did before. First of all blood samples may be collected.You ask why, we have a victim who's shot, so the blood isobviously his right? Wrong, suppose our actor cut himselfor was injured when he fired the gun? The samples can placesomeone else in the scene. We also must look for spent shellcasings from the gun. There may be projectiles which passedthrough the body and struck the walls or floor. If so theprojectiles must be recovered for later ballistics test should wefind a firearm at the scene or find one at a later time duringthe investigation. The possibility also exists that our victimmay not have been shot where his body was found. The entirehouse needs an in depth search. Was the gun our victim's?Was it taken from him during a struggle? Did the actor bringit with him? These are only some of the questions that needto be answered. Other things must be noted. Was the TV on,is there food on the table or on the stove. This is crucial iffood is found in the victim's stomach at the autopsy. Is it thesame? This could help establish a more accurate time of death.In addition to all the photographs and video taken a sketch ofscene must also be made. On that sketch all the evidence thatwas collected, the victim's body, blood stains, shell casings oranything important to the case must be measured in. This isuseful at time of trial to illustrate to the jury the position ofthese items within the scene as sometimes photographs do notshow these things in their proper prospective. A reason forthe crime may be able to be determined. Was it robbery, drugrelated, a domestic? These are things that may also be foundout at the crime scene.
