RECENT ADVANCEMENTS
HIGH-SPEED BALLISTICS PHOTOGRAPHY
Scientists can now use these high speed cameras to understand how bullet holes and gunshot wounds are created. This can help with an investigation by showing where the impact and exit wounds are and also the bullet trajectories, or how close someone was when they shot another person. The example above shows a high-speed picture of a bullet exiting a banana.
Scientists can now use these high speed cameras to understand how bullet holes and gunshot wounds are created. This can help with an investigation by showing where the impact and exit wounds are and also the bullet trajectories, or how close someone was when they shot another person. The example above shows a high-speed picture of a bullet exiting a banana.
3D FACIAL RECONSTRUCTION
This new advancement allows scientists to recreate what a face might have looked like from only the skull and some clay. The race, sex, and sometime even the age of the deceased person can be determined from their skull. The pieces of clay sticking out in the first picture are called depth markers and they are used to approximate the facial tissue thickness on the skull. The most difficult part of the facial reconstruction is with the eyes and the nose because of the vast number of possibilities of what they could have looked like. Although this method of identification is not yet legally admissible in court, it is very interesting how someone's face can be determined just from their remains.
This new advancement allows scientists to recreate what a face might have looked like from only the skull and some clay. The race, sex, and sometime even the age of the deceased person can be determined from their skull. The pieces of clay sticking out in the first picture are called depth markers and they are used to approximate the facial tissue thickness on the skull. The most difficult part of the facial reconstruction is with the eyes and the nose because of the vast number of possibilities of what they could have looked like. Although this method of identification is not yet legally admissible in court, it is very interesting how someone's face can be determined just from their remains.
DNA SEQUENCING
This vital process is important because it identifies criminals by using evidence left behind, like hair or skin samples. Teeth and old bones can also be analyzed when the other samples are too debased to use. Each person has unique DNA nucleobases, so these samples are read by the sequencer and it then identifies possible suspects.
This vital process is important because it identifies criminals by using evidence left behind, like hair or skin samples. Teeth and old bones can also be analyzed when the other samples are too debased to use. Each person has unique DNA nucleobases, so these samples are read by the sequencer and it then identifies possible suspects.
CARBON-14 DATING
Recently, Carbon-14 Dating has been used because of the fluctuation of radiation on the earth in the past 50-100 years. This process is used to determine the age of objects and remains up to 50,000 years old. By measuring the Carbon-14 levels in human remains, scientists can figure out the year a person was born in and the year they died in.
Recently, Carbon-14 Dating has been used because of the fluctuation of radiation on the earth in the past 50-100 years. This process is used to determine the age of objects and remains up to 50,000 years old. By measuring the Carbon-14 levels in human remains, scientists can figure out the year a person was born in and the year they died in.
FINGERPRINT TECHNOLOGY
Fingerprints have been left at crime scenes for a long time, and some are even present that people cannot detect with a naked eye. Latent fingerprints, or the ones not easily seen, can now be detected using different types of lights, lasers, and x-ray equipment instead of brushes, which were not very reliable. Different chemicals can also be used to help identify fingerprints such as iodine, ninhydrin reagents, silver nitrate, fluorescent reagents, and super glue. Chemical enhancement technology has also allowed scientists to look for ridge characteristics in the fingerprint itself and figure out the person who left it.
Fingerprints have been left at crime scenes for a long time, and some are even present that people cannot detect with a naked eye. Latent fingerprints, or the ones not easily seen, can now be detected using different types of lights, lasers, and x-ray equipment instead of brushes, which were not very reliable. Different chemicals can also be used to help identify fingerprints such as iodine, ninhydrin reagents, silver nitrate, fluorescent reagents, and super glue. Chemical enhancement technology has also allowed scientists to look for ridge characteristics in the fingerprint itself and figure out the person who left it.
IMAGE ENHANCEMENTS
Enhancements in images like imprints (patterns left on hard surfaces) and impressions (three-dimensional indentations) have allowed scientists to collect a bounty of helpful data. New photographic techniques allow the images taken to be enhanced to let researchers view more details through different filters. Digital photography can intensify the image taken of things like bite marks on a victim. Other new digital techniques can also significantly assist in identifying faces in poor quality videos or pictures taken of a suspect. Various chemicals can also help bring out substances like blood and minerals from a shoe, as seen above with an imprint.
Enhancements in images like imprints (patterns left on hard surfaces) and impressions (three-dimensional indentations) have allowed scientists to collect a bounty of helpful data. New photographic techniques allow the images taken to be enhanced to let researchers view more details through different filters. Digital photography can intensify the image taken of things like bite marks on a victim. Other new digital techniques can also significantly assist in identifying faces in poor quality videos or pictures taken of a suspect. Various chemicals can also help bring out substances like blood and minerals from a shoe, as seen above with an imprint.
HANDWRITING ANALYSIS
Writing is an every day task performed by almost everyone. After many years of writing, the writer focuses more on the content of what is being written, not the form of their writing, so it becomes a subconscious act. Scientists analyze writing by the pressure of the pen, spacing between words and letters, height relationships, and position of characters on the baseline, and more. Not all handwriting can be identified, like tracing, as seen above. The first signature is "Marvin Johnson"'s actual signature. As you can see, the one directly below is an exact copy which is virtually impossible for one person to reproduce without tracing.
Writing is an every day task performed by almost everyone. After many years of writing, the writer focuses more on the content of what is being written, not the form of their writing, so it becomes a subconscious act. Scientists analyze writing by the pressure of the pen, spacing between words and letters, height relationships, and position of characters on the baseline, and more. Not all handwriting can be identified, like tracing, as seen above. The first signature is "Marvin Johnson"'s actual signature. As you can see, the one directly below is an exact copy which is virtually impossible for one person to reproduce without tracing.
FIGURE 1: PASSIVE STAIN
FIGURE 2: LUMINOL REACTING WITH IRON AND HEMOGLOBIN
BLOODSTAIN PATTERN ANALYSIS
Blood can be ejected from the body in various ways and leave different patterns. Passive stains, like drops or pools of blood seen above, are usually left behind from an injured person (FIGURE 1). They are usually a result of gravity acting upon the wounded body. Transfer stains are from another object coming into contact with blood, like if a body was being dragged and if it left behind a trail of blood. The last type of stain is an impact stain which is in the form of a splatter when blood is projected through the air, like when someone gets shot or from a gushing wound. Some bloodstains can be latent and are only seen with chemical reagents, like Luminol, that creates a blue illumination to allow the blood to be seen (FIGURE 2). This is able to happen because the Luminol reacts with the iron and hemoglobin in the blood.
Blood can be ejected from the body in various ways and leave different patterns. Passive stains, like drops or pools of blood seen above, are usually left behind from an injured person (FIGURE 1). They are usually a result of gravity acting upon the wounded body. Transfer stains are from another object coming into contact with blood, like if a body was being dragged and if it left behind a trail of blood. The last type of stain is an impact stain which is in the form of a splatter when blood is projected through the air, like when someone gets shot or from a gushing wound. Some bloodstains can be latent and are only seen with chemical reagents, like Luminol, that creates a blue illumination to allow the blood to be seen (FIGURE 2). This is able to happen because the Luminol reacts with the iron and hemoglobin in the blood.
HAIR ANALYSIS
All different types of hair have different internal and external features to differentiate from one animal to another. There are also microscopic differences between the hairs of different races. Hair analysis is a very useful tactic because along with knowing the race of a suspect, it can determine the age of the person who left the hair behind. Already being aware that the suspect is going to be a white man or woman around the age of 40 will expedite the case. This analysis is also helpful because hairs are transferred during physical contact which can link a suspect to a crime scene. Under a microscope, the removal method of the hair can be determined, whether it just fell out or if it was forcibly removed, like the one pictured above. The figure is a microscopic image that shows stretching and damage to the root area which affirms to scientists that it was in some way removed by force.
All different types of hair have different internal and external features to differentiate from one animal to another. There are also microscopic differences between the hairs of different races. Hair analysis is a very useful tactic because along with knowing the race of a suspect, it can determine the age of the person who left the hair behind. Already being aware that the suspect is going to be a white man or woman around the age of 40 will expedite the case. This analysis is also helpful because hairs are transferred during physical contact which can link a suspect to a crime scene. Under a microscope, the removal method of the hair can be determined, whether it just fell out or if it was forcibly removed, like the one pictured above. The figure is a microscopic image that shows stretching and damage to the root area which affirms to scientists that it was in some way removed by force.