With the present technology and techniques they could test it now, but they would not have done that in the 90s.
DNA Revisited
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Unfortunately(and I didn't know this before) I think testing the garrote is no longer possible.:banghead:
At least that's what I understand from the following (arghhhhhh and I was hoping they could do tons of tests now and maybe find something new)
http://www.jonbenetindexguide.com/09212001Depo-SteveThomas.htm
Q. Were you ever told by anyone that
22 the reason the Ramsey lawyers were allowed to
23 see the garrote and to see the firsthand
24 original of the ransom note is because both
25 items were getting ready to be tested in a
1 fashion that would be destructive and that
2 from a strategical standpoint somewhere down
3 the road it might be advantageous for the
4 defense lawyers not to be able to claim foul
5 by saying that they didn't have a chance to
6 observe these pieces of evidence before they
7 were destroyed? Did you ever hear that
8 explanation given as to why the Ramsey
9 lawyers were allowed to look at those two
10 items?
I believe what ST was referring to here in terms of the garrote, was the paint brush handle only.
This along with the RN was going to be subject to fingerprint analysis using chemical developers.
Today a decision would have to be made whether to attempt to retrieve fingerprints through the use of developers or whether to swab surfaces in an attempt to salvage material for DNA analysis. The two processes are mutually incompatible, as some fingerprint developers destroy material that could potentially be used for DNA examination, and swabbing is likely to make fingerprint identification impossible. Furthermore, some techniques will make additional fingerprint analysis using a different method impossible; superglue fuming is one example.
In the late 90's DNA testing at that level was not an option, but the decision to use a method that would make further fingerprint testing impossible was made.
In the Ramsey case I dont know what method they were using, and although further testing may not be possible on the RN and the paint brush handle in terms of fingerprint and DNA analysis, the rope definitely would still be testable for trace DNA. Also, depending on precisely what method was used, it may still be possible to do touch DNA testing on all of the items in question despite further fingerprint analysis being impossible.
Trace DNA profiles have been developed, even after processing for fingerprints, using cyanoacrylate fuming and metal deposition techniques on a variety of items, including knife handles. It is speculated that rather than jeopardize recovery of DNA bearing cells, the application of a very thin layer of acrylic through the fingerprint fuming process may help seal cells in place, to be removed later though swabbing. Conversely, rough wooden handles on knives may have resulted in very poor adhesion of fingerprint reagents, making their use non-DNA-destructive.
-Ray A. Wickenheiser, Journal of Forensic Sciences
Latent prints are made visible using a variety of chemical and physical methods. Nonporous surfaces, (such as glass), are examined or "processed" using methods including cyanoacrylate ester ("superglue") fuming, luminescence (laser), dye staining, and traditional brush and powder. Porous surfaces, (such as paper), may be processed using chemical methods such as diazafluoren-one, ninhydrin, and physical developer. The exact processing sequence will depend upon a number of variables including surface type, environmental factors, the length of time elapsed since suspected handling, and the potentially destructive effects of each technique that would preclude subsequent examination by other methods or for other types of evidence.
Lasers are used to visualize fingerprints. Items are "superglued" and the superglue residue is stained with a luminescent dye. The item is then examined in a darkened room using the laser. Goggles are worn to filter out the colors of light the laser produces directly. Latent prints visualized with the laser are not visible to the naked eye in ordinary room light, and must be photographed.
http://www.doj.state.wi.us/DLES/crimelabs/ident.asp
This is from a recent interview between Evidence Technology Magazine and Joe Minor-Technical DNA Manager & Special Agent-Forensic Scientist Supervisor, Tennessee Bureau of Investigation:
(It would be interesting to know specifically what collection and handling techniques were used in the Ramsey case – I’m guessing it wasn’t pretty, especially in light of what we know about the semi-sterile (at best) nail clippers. The problem with applying sensitive DNA testing to old evidence is that the evidence was not collected and handled with today’s knowledge of how easily contamination and cross-contamination can occur with skin cells.)
EVIDENCE TECHNOLOGY: When you teach classes for crime-scene investigators, what are some of the key points in DNA collection that you cover?
MINOR: I talk to them about basic concepts, like proper recognition and preservation of the evidence. We discuss the fundamentals of packaging biological evidence and how that should be packaged in breathable containers. And everything needs to be packaged separately. Even if they think that it is the victim’s clothes and it is all the victim’s blood and it wouldn’t hurt to package a few of those similar items together… I say: Stop and think about that. Don’t do it. Package everything separately so there is no cross-transfer.
EVIDENCE TECHNOLOGY: Does your laboratory encourage the submission of swabbings from the crime scene?
MINOR: No, instead of swabbing things, we would prefer—if at all possible—that they submit the entire item. You may get different responses from your readers on that. If it is an immovable object that they obviously cannot submit to us, we will have to deal with the swabbings. Otherwise, we would much rather have the gun submitted, for example, so that we can look for blood in the laboratory and do the swabbing—rather than having ten swabs that someone else took from a gun. With touch DNA really taking hold in this field—that is, testing epithelial cells (skin cells)—we would definitely prefer to have the opportunity to swab items ourselves rather than have someone else do it.
EVIDENCE TECHNOLOGY: Why?
MINOR: Unlike blood, where there usually is an obvious, reddish-brown stain that you can swab, touch DNA is totally invisible. It’s just skin cells. So you have to just learn to approach those cases differently. Working directly with people in our latent-prints section here at the lab, we can collaborate and decide what locations have been handled by the person—and what locations we want to stay away from and save for the latent-print people so that we are not swabbing up a print that you cannot see with the naked eye.
EVIDENCE TECHNOLOGY: How much success have you had with getting good results from touch DNA?
MINOR: It has been pretty successful when collected from things like trigger guards and guns, knives, and tools that have been handled. It is working. If someone transfers epithelial cells on a rough surface and we happen to swab it up, it is going to type.
EVIDENCE TECHNOLOGY: The technology you are using is getting very sensitive, isn’t it?
MINOR: Yes—which brings up another thing that I tell folks about changing their gloves frequently to prevent cross-contamination. It is pretty well understood that when you are at a scene collecting bloody items, you don’t want to touch something, get blood on the gloves, and then handle another item. Everybody knows that. But now we need to start thinking about skin cells. If you are wearing a glove and you handle something that may have been handled by somebody else, you may need to think about changing gloves before you touch the next item. As a matter of fact, if you put on a pair of clean gloves and you inadvertently bring your finger up and scratch your face or nose, then your skin cells are going to be on that glove, and that can go to the next item you touch, as well.
EVIDENCE TECHNOLOGY: How about fingerprint brushes? Can they cause cross-contamination of DNA?
MINOR: Well, that’s a very good question. As a matter of fact, one point in our laboratory’s policy states that items that have been processed for latent prints will not be examined for touch DNA. Most people are not using disposable brushes, from what we understand. The problem with that is going to be if you dust with a brush that has dusted blood samples from a previous case and it gets transferred to an item. If you are lucky enough to get a DNA profile from that item, it could be very problematic because then you have a profile that might not match the suspect because it really came from another crime.
http://www.evidencemagazine.com/index.php?option=com_content&task=view&id=160&Itemid=9
(It would be interesting to know specifically what collection and handling techniques were used in the Ramsey case – I’m guessing it wasn’t pretty, especially in light of what we know about the semi-sterile (at best) nail clippers. The problem with applying sensitive DNA testing to old evidence is that the evidence was not collected and handled with today’s knowledge of how easily contamination and cross-contamination can occur with skin cells.)
EVIDENCE TECHNOLOGY: When you teach classes for crime-scene investigators, what are some of the key points in DNA collection that you cover?
MINOR: I talk to them about basic concepts, like proper recognition and preservation of the evidence. We discuss the fundamentals of packaging biological evidence and how that should be packaged in breathable containers. And everything needs to be packaged separately. Even if they think that it is the victim’s clothes and it is all the victim’s blood and it wouldn’t hurt to package a few of those similar items together… I say: Stop and think about that. Don’t do it. Package everything separately so there is no cross-transfer.
EVIDENCE TECHNOLOGY: Does your laboratory encourage the submission of swabbings from the crime scene?
MINOR: No, instead of swabbing things, we would prefer—if at all possible—that they submit the entire item. You may get different responses from your readers on that. If it is an immovable object that they obviously cannot submit to us, we will have to deal with the swabbings. Otherwise, we would much rather have the gun submitted, for example, so that we can look for blood in the laboratory and do the swabbing—rather than having ten swabs that someone else took from a gun. With touch DNA really taking hold in this field—that is, testing epithelial cells (skin cells)—we would definitely prefer to have the opportunity to swab items ourselves rather than have someone else do it.
EVIDENCE TECHNOLOGY: Why?
MINOR: Unlike blood, where there usually is an obvious, reddish-brown stain that you can swab, touch DNA is totally invisible. It’s just skin cells. So you have to just learn to approach those cases differently. Working directly with people in our latent-prints section here at the lab, we can collaborate and decide what locations have been handled by the person—and what locations we want to stay away from and save for the latent-print people so that we are not swabbing up a print that you cannot see with the naked eye.
EVIDENCE TECHNOLOGY: How much success have you had with getting good results from touch DNA?
MINOR: It has been pretty successful when collected from things like trigger guards and guns, knives, and tools that have been handled. It is working. If someone transfers epithelial cells on a rough surface and we happen to swab it up, it is going to type.
EVIDENCE TECHNOLOGY: The technology you are using is getting very sensitive, isn’t it?
MINOR: Yes—which brings up another thing that I tell folks about changing their gloves frequently to prevent cross-contamination. It is pretty well understood that when you are at a scene collecting bloody items, you don’t want to touch something, get blood on the gloves, and then handle another item. Everybody knows that. But now we need to start thinking about skin cells. If you are wearing a glove and you handle something that may have been handled by somebody else, you may need to think about changing gloves before you touch the next item. As a matter of fact, if you put on a pair of clean gloves and you inadvertently bring your finger up and scratch your face or nose, then your skin cells are going to be on that glove, and that can go to the next item you touch, as well.
EVIDENCE TECHNOLOGY: How about fingerprint brushes? Can they cause cross-contamination of DNA?
MINOR: Well, that’s a very good question. As a matter of fact, one point in our laboratory’s policy states that items that have been processed for latent prints will not be examined for touch DNA. Most people are not using disposable brushes, from what we understand. The problem with that is going to be if you dust with a brush that has dusted blood samples from a previous case and it gets transferred to an item. If you are lucky enough to get a DNA profile from that item, it could be very problematic because then you have a profile that might not match the suspect because it really came from another crime.
http://www.evidencemagazine.com/index.php?option=com_content&task=view&id=160&Itemid=9
COLORADO CORONERS ASSOCIATION NEWSLETTER
SUMMER 2007
From CBI
Trace DNA Precautions
By The Colorado Bureau of Investigation Laboratories
Have you ever thought about what happens to objects when you breathe on them, cough or sneeze near them, talk over them, or even adjust your glasses or wipe your brow while wearing gloves? All of these offer the potential to deposit your DNA on surfaces, usually unknowingly!
Remember when we used to wear gloves and masks to avoid getting something from a body or scene? Technology has changed the way we need to do our business.
Our intent is to provide a brief overview of what can happen at scenes, in a lab, morgue or autopsy room, and what information can be obtained from DNA as analyzed at the Colorado Bureau of Investigation.
What are some precautions we can all take to minimize this trace DNA from ourselves? This is the classic two-edged sword. We have the sensitivity to get identifiable DNA from someones finger touching a light switch or doorknob (such as a perpetrator); however, this same sensitivity can allow our own DNA to be found during an analysis!
Since we are analyzing small amounts of DNA (125 cells may be adequate to get a full profile), there is also the potential of removing DNA from an item that may have significance to the case.
Lets address DNA concerns at the scene, in the lab, morgue or autopsy room and finally the information we can obtain from DNA analysis.
Scene:
The weapon such as the grip of a firearm, the trigger of a firearm, or the handle of a knife may have DNA from the person who handled that weapon.
The body of the deceased may have DNA from someone who has manually strangled the victim. A ligature used to bind or strangle may contain DNA.
Clothing items may contain DNA of someone who has handled the clothing of the deceased.
Skin touched in the process of moving a victim in some fashion or dressing or undressing a victim may have foreign DNA.
A suspect may also leave DNA if they happen to cough sneeze, or spit accidentally (while talking) over or on the deceased. The doorknob used to enter and exit the room or other objects that may be present in the path from the entry way to the body.
Morgue, autopsy room, or lab:
The items mentioned above need to be handled with caution if they do end up in one of these places, especially the clothing items. Remember the removal of DNA is as significant as the addition of your DNA to an object.
We need to think about the potential for contamination from previous deceased, autopsies, or evidence; even scissors that are used to cut clothing from one body may transfer DNA to a second body or object if not cleaned.
Results that may come from evidence analysis at CBI:
The presence of DNA from the victim/deceased where it might be expected.
The presence of DNA from someone other than the deceased.
A mixture of DNA from one or more individuals, sometimes as a major component and a minor component.
The presence of male DNA utilizing analysis of the Y chromosome (Y-STR).
Remember that there are many sources of DNA and blood is only one of them. Among the other sources are skin cells left on an object, other body fluids, muscle tissue, dental pulp, and marrow in long bones, for example.
http://coloradocoroners.org/newsletters/summer2007.pdf
SUMMER 2007
From CBI
Trace DNA Precautions
By The Colorado Bureau of Investigation Laboratories
Have you ever thought about what happens to objects when you breathe on them, cough or sneeze near them, talk over them, or even adjust your glasses or wipe your brow while wearing gloves? All of these offer the potential to deposit your DNA on surfaces, usually unknowingly!
Remember when we used to wear gloves and masks to avoid getting something from a body or scene? Technology has changed the way we need to do our business.
Our intent is to provide a brief overview of what can happen at scenes, in a lab, morgue or autopsy room, and what information can be obtained from DNA as analyzed at the Colorado Bureau of Investigation.
What are some precautions we can all take to minimize this trace DNA from ourselves? This is the classic two-edged sword. We have the sensitivity to get identifiable DNA from someones finger touching a light switch or doorknob (such as a perpetrator); however, this same sensitivity can allow our own DNA to be found during an analysis!
Since we are analyzing small amounts of DNA (125 cells may be adequate to get a full profile), there is also the potential of removing DNA from an item that may have significance to the case.
Lets address DNA concerns at the scene, in the lab, morgue or autopsy room and finally the information we can obtain from DNA analysis.
Scene:
The weapon such as the grip of a firearm, the trigger of a firearm, or the handle of a knife may have DNA from the person who handled that weapon.
The body of the deceased may have DNA from someone who has manually strangled the victim. A ligature used to bind or strangle may contain DNA.
Clothing items may contain DNA of someone who has handled the clothing of the deceased.
Skin touched in the process of moving a victim in some fashion or dressing or undressing a victim may have foreign DNA.
A suspect may also leave DNA if they happen to cough sneeze, or spit accidentally (while talking) over or on the deceased. The doorknob used to enter and exit the room or other objects that may be present in the path from the entry way to the body.
Morgue, autopsy room, or lab:
The items mentioned above need to be handled with caution if they do end up in one of these places, especially the clothing items. Remember the removal of DNA is as significant as the addition of your DNA to an object.
We need to think about the potential for contamination from previous deceased, autopsies, or evidence; even scissors that are used to cut clothing from one body may transfer DNA to a second body or object if not cleaned.
Results that may come from evidence analysis at CBI:
The presence of DNA from the victim/deceased where it might be expected.
The presence of DNA from someone other than the deceased.
A mixture of DNA from one or more individuals, sometimes as a major component and a minor component.
The presence of male DNA utilizing analysis of the Y chromosome (Y-STR).
Remember that there are many sources of DNA and blood is only one of them. Among the other sources are skin cells left on an object, other body fluids, muscle tissue, dental pulp, and marrow in long bones, for example.
http://coloradocoroners.org/newsletters/summer2007.pdf
TY, Sophie.
My personal view is that Mary Lacy was made aware of the limitations of touch DNA, such as outlined in the posts above, quite possibly by Bode Technology (or at least they should have.)
This makes her public exoneration of the Ramseys dishonest at the very least.
Sophie
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ITA Cynic. It just seems extraordinary that someone whose position would presumably require great legal talent would make so fundamentally flawed a decision - the ramifications of which go far beyond just the 'exoneration' of the Ramseys.
Hey Tadpole.
If she wasn't educated by Bode, she undoubtedly learned a thing or two at West Virginia University:
In fact, the prosecutor in the Ramsey case, Boulder County District Attorney Mary Lacy, learned about touch DNA when she attended a course here at the West Virginia University Forensic Science Initiative in the summer of 2007.
http://www.scientificamerican.com/article.cfm?id=experts-touch-dna-jonbenet-ramsey
If she didn't learn this, she certainly should have:
Strengths and Weaknesses
-CBI Laboratory Agent Schleicher
First, "touch DNA," like standard DNA and fingerprints for that matter, doesn't tell the investigator when the DNA was left on the evidence. It could have been left an hour ago or a week ago. Of course the investigator may be able to narrow down the time range based on certain facts of the particular case.
An example is a suspect's baseball cap left behind at a murder scene. The lab swabs the inside and outside of the hat. A DNA profile from two individuals is developed. Even if there's more DNA from one contributor than the other, you still can't say who was wearing the hat at the time of the murder.
Also, "touch DNA" is so sensitive that it's possible to pick up background DNA. For example, if a shirt is made by hand, then someone has touched the shirt even before it's packaged and sold. It's possible "touch DNA" could liberate these skin cells from the evidence, even though this person has nothing to do with the investigation.
And of course, "touch DNA" doesn't tell the investigator how the DNA made its way onto an item. It doesn't provide the culpable mental state of the individual that committed the crime.
It's up to the lawyers to argue whether the "touch DNA" is the result of a casual contact, or from the suspect forcefully grabbing the victim's shirt. The bottom line is that good police work is necessary to piece together the events surrounding the commission of the crime.
Schleicher wants agencies to be aware of the power and limitations of the technology. Agencies need to clearly understand the questions they want answered. Why is this piece of evidence important? What will it tell me about the commission of the crime? Law enforcement agencies just need to be prepared for the answers, even if the answers aren't what they were expecting.
http://www.policemag.com/Channel/Technology/Articles/Print/Story/2008/12/Just-a-Touch.aspx
Touch DNA has essentially the same issues that hair and fiber evidence have. They can have high probative value or they can border on meaningless depending on the circumstances of the case, the degree to which the crime scene was preserved , and techniques used to collect, store, and analyze the evidence.
I am familiar with "Touch DNA" and limitations to this technique which includes the following:
a. No body fluid has been identified for the samples tested. If a DNA profile is identified in a "touch" or "contact" area, the result may be from an individual with no relation to the crime.
b. The samples are limited imposing some technical limitations. A negative result could mean that an individual did not contact the item tested. A negative result could also mean too few cells were collected. The ISPR&D laboratory has shown that individuals shed cells with typable DNA at varied rates; absence of a results may not indicate absence of contact.
c. The presence of a high level of one DNA profile could also result in missing low level results
http://cspl.uis.edu/ILLAPS/Service/...Project/documents/Exhibit7toStateResponse.pdf
Evidence Handling Procedures
Once the evidence has been collected, there are several recommendations or considerations when packaging it for transmittal to the laboratory. Clothing items must be packaged in separate sealed paper bagsnot plastic. To avoid contamination, clothing items from the suspect should never be handled in the same area in which items from the victim are handled. All damp or blood-soaked items must be air-dried in a room away from air movement and traffic. Drying paper placed under damp clothing items should be submitted separately.
Hair:
The hair identification process involves the examination and comparison of hair characteristics along the entire length of the hair(s). Longer hairs have more characteristics to compare, and the greater the variation along the length, the greater the degree of significance.
The value of the evidence in establishing a particular association can be influenced by
· The probability that the association (or elimination)
was due to coincidence,
· The probability that the association (or elimination) was due to examiner error, and
· The probability that there is an alternative explanation for the evidence, such as secondary transfer, contamination, or deliberate planting.
It has also been stated that hair evidence is only of value when used in conjunction with other evidence.
Fiber:
Placing a suspect at the scene of a crime is an important element in criminal investigation. This can be achieved through the location of textile fibers similar to those from the victim's clothing or the crime scene on the clothing of the suspect, or through the discovery of fibers like those in the suspect's clothing at the crime scene.
Textile fibers can be exchanged between two individuals, between an individual and an object, and between two objects. When fibers are matched with a specific source (fabric from the victim, suspect, and/or scene), a value is placed on that association. This value is dependent on many factors, including the type of fiber found, the color or variation of color in the fiber, the number of fibers found, the location of fibers at the crime scene or on the victim, and the number of different fibers at the crime scene or on the victim that match the clothing of the suspect.
Whether a fiber is transferred and detected is dependent on the nature and duration of contact between the suspect and the victim or crime scene, the persistence of fibers after the transfer, and the type(s) of fabric involved in contact.
As discussed previously, fibers are considered a form of trace evidence that can be transferred from the clothing of a suspect to the clothing of a victim during the commission of a crime. Fibers can also transfer from a fabric source such as a carpet, bed, or furniture at a crime scene. These transfers can either be direct (primary) or indirect (secondary). A primary transfer occurs when a fiber is transferred from a fabric directly onto a victim's clothing, whereas a secondary transfer occurs when already transferred fibers on the clothing of a suspect transfer to the clothing of a victim. An understanding of the mechanics of primary and secondary transfer is important when reconstructing the events of a crime.
When two people come in contact or when contact occurs with an item from the crime scene, the possibility exists that a fiber transfer will take place. This does not mean that a fiber transfer will always take place. Certain types of fabric do not shed well (donor garments), and some fabrics do not hold fibers well (recipient garments). The construction and fiber composition of the fabric, the duration and force of contact, and the condition of the garment with regard to damage are important considerations.
An important consideration is the length of time between the actual physical contact and the collection of clothing items from the suspect or victim. If the victim is immobile, very little fiber loss will take place, whereas the suspect's clothing will lose transferred fibers quickly. The likelihood of finding transferred fibers on the clothing of the suspect a day after the alleged contact may be remote, depending on the subsequent use or handling of that clothing.
Textile fibers are transferred to the surface of a fabric either by direct transfer (primary transfer) or indirect transfer (secondary transfer). The likelihood of transfer depends on the types of fabric involved in the contact and the nature and duration of the contact. Studies have shown that transferred fibers are lost rather quickly, depending on the types of fabrics involved and on the movement of the clothing after contact. For example, the clothing of a homicide victim would tend to retain transferred fibers for a longer period of time because the victim is not moving.
Emergency personnel, medical examiners, and investigators must handle the victim's clothing carefully to minimize fiber loss. Fibers transferred onto the clothing of an assault victim or onto the suspect's clothing will be lost if the victim and suspect move about, brush the clothing, or wash the clothing. It is difficult to predict precisely how many fibers might remain on the clothing of a living victim or suspect after a given period of time, but it is important for investigators to retrieve and preserve the clothing from these individuals as soon as possible.
http://www.fbi.gov/hq/lab/fsc/backissu/july2000/deedric4.htm
I am familiar with "Touch DNA" and limitations to this technique which includes the following:
a. No body fluid has been identified for the samples tested. If a DNA profile is identified in a "touch" or "contact" area, the result may be from an individual with no relation to the crime.
b. The samples are limited imposing some technical limitations. A negative result could mean that an individual did not contact the item tested. A negative result could also mean too few cells were collected. The ISPR&D laboratory has shown that individuals shed cells with typable DNA at varied rates; absence of a results may not indicate absence of contact.
c. The presence of a high level of one DNA profile could also result in missing low level results
http://cspl.uis.edu/ILLAPS/Service/...Project/documents/Exhibit7toStateResponse.pdf
Evidence Handling Procedures
Once the evidence has been collected, there are several recommendations or considerations when packaging it for transmittal to the laboratory. Clothing items must be packaged in separate sealed paper bagsnot plastic. To avoid contamination, clothing items from the suspect should never be handled in the same area in which items from the victim are handled. All damp or blood-soaked items must be air-dried in a room away from air movement and traffic. Drying paper placed under damp clothing items should be submitted separately.
Hair:
The hair identification process involves the examination and comparison of hair characteristics along the entire length of the hair(s). Longer hairs have more characteristics to compare, and the greater the variation along the length, the greater the degree of significance.
The value of the evidence in establishing a particular association can be influenced by
· The probability that the association (or elimination)
was due to coincidence,
· The probability that the association (or elimination) was due to examiner error, and
· The probability that there is an alternative explanation for the evidence, such as secondary transfer, contamination, or deliberate planting.
It has also been stated that hair evidence is only of value when used in conjunction with other evidence.
Fiber:
Placing a suspect at the scene of a crime is an important element in criminal investigation. This can be achieved through the location of textile fibers similar to those from the victim's clothing or the crime scene on the clothing of the suspect, or through the discovery of fibers like those in the suspect's clothing at the crime scene.
Textile fibers can be exchanged between two individuals, between an individual and an object, and between two objects. When fibers are matched with a specific source (fabric from the victim, suspect, and/or scene), a value is placed on that association. This value is dependent on many factors, including the type of fiber found, the color or variation of color in the fiber, the number of fibers found, the location of fibers at the crime scene or on the victim, and the number of different fibers at the crime scene or on the victim that match the clothing of the suspect.
Whether a fiber is transferred and detected is dependent on the nature and duration of contact between the suspect and the victim or crime scene, the persistence of fibers after the transfer, and the type(s) of fabric involved in contact.
As discussed previously, fibers are considered a form of trace evidence that can be transferred from the clothing of a suspect to the clothing of a victim during the commission of a crime. Fibers can also transfer from a fabric source such as a carpet, bed, or furniture at a crime scene. These transfers can either be direct (primary) or indirect (secondary). A primary transfer occurs when a fiber is transferred from a fabric directly onto a victim's clothing, whereas a secondary transfer occurs when already transferred fibers on the clothing of a suspect transfer to the clothing of a victim. An understanding of the mechanics of primary and secondary transfer is important when reconstructing the events of a crime.
When two people come in contact or when contact occurs with an item from the crime scene, the possibility exists that a fiber transfer will take place. This does not mean that a fiber transfer will always take place. Certain types of fabric do not shed well (donor garments), and some fabrics do not hold fibers well (recipient garments). The construction and fiber composition of the fabric, the duration and force of contact, and the condition of the garment with regard to damage are important considerations.
An important consideration is the length of time between the actual physical contact and the collection of clothing items from the suspect or victim. If the victim is immobile, very little fiber loss will take place, whereas the suspect's clothing will lose transferred fibers quickly. The likelihood of finding transferred fibers on the clothing of the suspect a day after the alleged contact may be remote, depending on the subsequent use or handling of that clothing.
Textile fibers are transferred to the surface of a fabric either by direct transfer (primary transfer) or indirect transfer (secondary transfer). The likelihood of transfer depends on the types of fabric involved in the contact and the nature and duration of the contact. Studies have shown that transferred fibers are lost rather quickly, depending on the types of fabrics involved and on the movement of the clothing after contact. For example, the clothing of a homicide victim would tend to retain transferred fibers for a longer period of time because the victim is not moving.
Emergency personnel, medical examiners, and investigators must handle the victim's clothing carefully to minimize fiber loss. Fibers transferred onto the clothing of an assault victim or onto the suspect's clothing will be lost if the victim and suspect move about, brush the clothing, or wash the clothing. It is difficult to predict precisely how many fibers might remain on the clothing of a living victim or suspect after a given period of time, but it is important for investigators to retrieve and preserve the clothing from these individuals as soon as possible.
http://www.fbi.gov/hq/lab/fsc/backissu/july2000/deedric4.htm
Well...so much for not handling the victim's clothes at the same time as the suspect's. Her father was allowed free-range over the crime scene (as was everyone else in the house that day) and carried his daughter up from the basement. And her mother was allowed to throw herself on her daughter's body.
Because of the publicity DNA testing has received, some people may think that if a DNA result is reported, this is conclusive proof that an individual committed a crime. However, the DNA result cannot in itself state anything about the importance of the result in a criminal case. For example, if a suspects DNA is found at a crime, there is no way to determine when the biological sample was deposited. This evidence must be considered by the jury along with other important facts of the case relating to how the DNA evidence may have been produced. As the sensitivity of DNA testing increases and techniques to detect DNA present in extremely small quantities, such as touch DNA techniques, are applied to evidence, the interpretation of this data becomes more critical.
The Real World of a Forensic Scientist Henry Lee
The Real World of a Forensic Scientist Henry Lee
Sound familiar?
The nun's 10 individual nail clippings had been placed together in a solution, dissolved, and then tested for DNA, making it impossible to determine if the male DNA had been on the top, sides, or beneath the victim's nails.
Assistant Lucas County Prosecutor J. Christopher Anderson said the amount of DNA on her fingernails was 37 picograms, or 37 trillionths of a gram - "a very, very tiny amount."
He said the coroner's office in 1980 used scissors to clip the nails and did not sanitize the scissors between uses. The DNA could have come from the scissors, someone touching her hand, or someone coughing or sneezing in the room, he said.
Mr. Anderson said the prosecutor's office performed DNA tests on 54 people before Robinson's 2006 trial and was unable to find a match with the crime scene evidence.
http://www.toledoblade.com/apps/pbcs.dll/article?AID=/20090716/NEWS02/907160313/0/columnist26
The nun's 10 individual nail clippings had been placed together in a solution, dissolved, and then tested for DNA, making it impossible to determine if the male DNA had been on the top, sides, or beneath the victim's nails.
Assistant Lucas County Prosecutor J. Christopher Anderson said the amount of DNA on her fingernails was 37 picograms, or 37 trillionths of a gram - "a very, very tiny amount."
He said the coroner's office in 1980 used scissors to clip the nails and did not sanitize the scissors between uses. The DNA could have come from the scissors, someone touching her hand, or someone coughing or sneezing in the room, he said.
Mr. Anderson said the prosecutor's office performed DNA tests on 54 people before Robinson's 2006 trial and was unable to find a match with the crime scene evidence.
http://www.toledoblade.com/apps/pbcs.dll/article?AID=/20090716/NEWS02/907160313/0/columnist26
State Lab Must Fix Errors, Seek New Jovin Clues
November 17, 2009
The recent revelation that the male DNA found in the blood under Suzanne Jovin's fingernails came from a former technician in the State Police Forensic Laboratory is enormously disappointing. Indeed, it's more than disappointing; it's devastating and constitutes an enormous setback in the star-crossed investigation of the murder of the Yale student 11 years ago.
There was always the possibility, as the prosecutors warned, that the DNA could have come from casual contact with a friend and be unrelated to the crime. But there was also the possibility it came from the killer and would eventually connect him to the crime. For many, it represented the best evidence in the case, the evidence most likely to lead to an arrest. Now it turns out to have been the result of lab contamination.
Jovin was stabbed 17 times in the head and neck at about 9:45 p.m. on Dec. 4, 1998, in a residential neighborhood of New Haven two miles from the Yale campus. For some inexplicable reason, the scrapings from the undersides of her fingernails literally the very first place one would look for the DNA of the killer were not tested until more than two years later. In October 2001, the prosecutors announced that DNA from an unknown male was found in the scrapings.
The latest revelation raises many questions about the lab's procedures for handling evidence. It was bad enough that it took more than two years for the scrapings to be tested. It is incomparably worse that the DNA found in the scrapings is that of a former lab technician who handled the case materials. It is still worse that it took more than eight years for the lab to discover the contamination. Whatever caused these huge errors must be corrected immediately.
The revelation came as a shock to the team of former state police officers now investigating the case. Created 2 1/2 years ago and consisting of four former members of the state police major crime squad, the team, led by John Mannion, has pursued a number of leads ignored by previous investigators. Speaking of the revelation, Mannion reportedly said, "It certainly was a shock to us ... another in the litany of errors in this case. ... It's another huge bump in the road."
http://siliconinvestor.advfn.com/readmsg.aspx?msgid=26104336
November 17, 2009
The recent revelation that the male DNA found in the blood under Suzanne Jovin's fingernails came from a former technician in the State Police Forensic Laboratory is enormously disappointing. Indeed, it's more than disappointing; it's devastating and constitutes an enormous setback in the star-crossed investigation of the murder of the Yale student 11 years ago.
There was always the possibility, as the prosecutors warned, that the DNA could have come from casual contact with a friend and be unrelated to the crime. But there was also the possibility it came from the killer and would eventually connect him to the crime. For many, it represented the best evidence in the case, the evidence most likely to lead to an arrest. Now it turns out to have been the result of lab contamination.
Jovin was stabbed 17 times in the head and neck at about 9:45 p.m. on Dec. 4, 1998, in a residential neighborhood of New Haven two miles from the Yale campus. For some inexplicable reason, the scrapings from the undersides of her fingernails literally the very first place one would look for the DNA of the killer were not tested until more than two years later. In October 2001, the prosecutors announced that DNA from an unknown male was found in the scrapings.
The latest revelation raises many questions about the lab's procedures for handling evidence. It was bad enough that it took more than two years for the scrapings to be tested. It is incomparably worse that the DNA found in the scrapings is that of a former lab technician who handled the case materials. It is still worse that it took more than eight years for the lab to discover the contamination. Whatever caused these huge errors must be corrected immediately.
The revelation came as a shock to the team of former state police officers now investigating the case. Created 2 1/2 years ago and consisting of four former members of the state police major crime squad, the team, led by John Mannion, has pursued a number of leads ignored by previous investigators. Speaking of the revelation, Mannion reportedly said, "It certainly was a shock to us ... another in the litany of errors in this case. ... It's another huge bump in the road."
http://siliconinvestor.advfn.com/readmsg.aspx?msgid=26104336
Here we have no DNA evidence linking the accused to the crime, as a matter of fact, the DNA points to two women as the assailants.
What would the Boulder DA's office do? Exoneration letter?
(The man was found guilty, and all appeals exhausted.)
Forensic evidence presented at a hearing into the murder of Janelle Patton on Norfolk Island has shown no DNA link to the New Zealand man accused of killing her.
Nelson chef Glenn McNeill has entered no plea to the charge of killing the 29-year old waitress on Norfolk Island in 2002.
The court has heard expert testimony from scientists who tested Miss Patton's clothing for DNA traces. Of more than 100 samples, they were unable to find the accused's profile on any of them.
However, analysis of Miss Patton's underwear found evidence of a mixed DNA profile from two females.
A swab taken from a car found on a property used by McNeill at the time of the murder did produce male DNA - but not that of the accused.
The pathologist who examined Janelle Patton's body told the court that 35 separate injuries contributed to her death.
Forensic pathologist Allan Cala conducted the post mortem examination on Ms Patton's body in April 2002.
Dr Cala told the committal hearing that multiple injuries caused Ms Patton's death, the most serious of which was a stab wound to the chest.
He also identified 34 other injuries to her head, neck, torso and limbs which led to her death.
McNeill was arrested in February and charged with murdering Janelle Patton, whose death was the first murder recorded on the self-governing island in 150 years.
The body of the 29-year-old restaurant manager was found wrapped in plastic at a picnic spot on Easter Sunday 2002.
http://www.nzherald.co.nz/norfolk-island/news/article.cfm?l_id=500686&objectid=10395220&pnum=1
(The primary evidence against the accused were fingerprints found on the plastic she was partially wrapped in.)
http://abc.gov.au/news/stories/2007/02/19/1851593.htm
DNA from skin cells has no business dictating the course of an investigation if the sum of all other evidence points elsewhere. As I've pointed out earlier, the prosecution in the Casey Anthony case is not cowering in fear as it faces "unknown DNA."
These prosecutors have confidence in their skills and in their case, and perhaps most importantly, the case is not in Boulder.
[ame]http://www.youtube.com/watch?v=UmBoNzsRp0s[/ame]
What would the Boulder DA's office do? Exoneration letter?
(The man was found guilty, and all appeals exhausted.)
Forensic evidence presented at a hearing into the murder of Janelle Patton on Norfolk Island has shown no DNA link to the New Zealand man accused of killing her.
Nelson chef Glenn McNeill has entered no plea to the charge of killing the 29-year old waitress on Norfolk Island in 2002.
The court has heard expert testimony from scientists who tested Miss Patton's clothing for DNA traces. Of more than 100 samples, they were unable to find the accused's profile on any of them.
However, analysis of Miss Patton's underwear found evidence of a mixed DNA profile from two females.
A swab taken from a car found on a property used by McNeill at the time of the murder did produce male DNA - but not that of the accused.
The pathologist who examined Janelle Patton's body told the court that 35 separate injuries contributed to her death.
Forensic pathologist Allan Cala conducted the post mortem examination on Ms Patton's body in April 2002.
Dr Cala told the committal hearing that multiple injuries caused Ms Patton's death, the most serious of which was a stab wound to the chest.
He also identified 34 other injuries to her head, neck, torso and limbs which led to her death.
McNeill was arrested in February and charged with murdering Janelle Patton, whose death was the first murder recorded on the self-governing island in 150 years.
The body of the 29-year-old restaurant manager was found wrapped in plastic at a picnic spot on Easter Sunday 2002.
http://www.nzherald.co.nz/norfolk-island/news/article.cfm?l_id=500686&objectid=10395220&pnum=1
(The primary evidence against the accused were fingerprints found on the plastic she was partially wrapped in.)
http://abc.gov.au/news/stories/2007/02/19/1851593.htm
DNA from skin cells has no business dictating the course of an investigation if the sum of all other evidence points elsewhere. As I've pointed out earlier, the prosecution in the Casey Anthony case is not cowering in fear as it faces "unknown DNA."
These prosecutors have confidence in their skills and in their case, and perhaps most importantly, the case is not in Boulder.
[ame]http://www.youtube.com/watch?v=UmBoNzsRp0s[/ame]
Hiya cynic.
TY for the link.
I was wondering that, if in our daily activities, we do contact so many sources of dna.
Not, just through primary contact, but by sitting on someone's couch or using a handtowel, touching surfaces.
With recent advances in dna technology, 'unknown dna' provides that opportunity for defense 'expert testimony'.
You're welcome Tadpole.
Probably the most impressive transfer experiment was the one involving transfer of DNA via a towel. Cells containing DNA were transferred to a towel, then to an individuals face and then to a glove. (A usable DNA profile was obtained by swabbing the glove.)
http://www.bioforensics.com/conference07/Transfer/Taylor&Johnson%20Study.pdf
How should we treat DNA evidence obtained from skin cells?
Because of the mobility of this DNA, it is not possible that it should carry the same weight as DNA from blood, urine, or semen. It should be of approximately the same value as hair and fiber, and of lesser significance than fingerprint evidence.
As a matter of fact, there is at least one DNA expert that agrees with me.
The DNA vs Fingerprints Debate
This raises the question, which of the two types is the stronger evidence? Answer: Fingerprints - and I say this as a DNA expert.
We also consider the nature of the transfer of evidence. If I were to touch a smooth surface such as a wall, I would deposit DNA and leave some fingerprints behind on the wall. This is called direct or primary transfer. However, if someone was to come along and wipe that wall with a cloth, it would remove my DNA onto the cloth and wipe the fingerprint off. If that person then uses that cloth to wipe the door handle, my DNA can then be transferred on to that door handle. Therefore, my DNA could be recovered from that handle without me ever coming into contact with it. This is referred to as indirect or secondary transfer. In this example, my DNA is transferred, but my fingerprint is not. This means that if my fingerprint is found on a surface, then I must have touched that surface; whereas, if my DNA is found on a surface, then I may have come into contact with that surface or it got there by secondary transfer.
-Graham Williams
http://www2.hud.ac.uk/sas/comment/gw260609.php
I dont doubt that unknown DNA will be introduced as the centerpiece of reasonable doubt in many future trials as defense lawyers try to manipulate jurors indoctrinated by CSI misinformation.
Perhaps this may ultimately lead to the necessity of a Supreme Court decision relating to the admissibility of skin cell based DNA, or at least a ruling relating to its probative value.
Hi cynic.
That's scary, a good performance in court, selected experts, and the CSI
jurists and populace, myself included. eeek.
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