Basic structure of DNA
The jurors requested read back of virtually all the DNA evidence presented at trial. Felicia Burke and Annette McCall presented all the prosecution's DNA testing evidence. Sprocket
Continued from Part II, Prosecution Witnesses 11-18....
PROSECUTION WITNESSES CONTINUED
19. FELICIA BURKE
Forensic scientist at Orange Co. Crime Lab since (I believe) 2001. Former name Felicia Gardner. She used to go by Felicia Gardner(sp?) Currently assigned to DNA section. Explains her training, background, current job and duties. Explains the process of DNA analysis and how it begins.
She met with detectives when she started the case. Received evidence from the evidence source location in the DNA laboratory. Explains the steps to get the case evidence, their evidence control unit and who has access to evidence locations.
At the crime lab where she works, crime evidence is tracked by a number called an FR number, (forensic report) number. Then the case can also have item numbers, for different pieces of evidence. The FR number is assigned by evidence control or by a clerical unit. Also explained when she gets evidence it’s sealed. Explains what sealed means to her, that it includes initials and date. Explains evidence tags that were in use at the time. After she examined evidence, she prepared a report. FR # is 0843964. ... At that time we were still using evidence tags.
Burke’s testimony was interrupted to take the testimony of Dr. Pena, who performed the autopsy.
20. DR. LOUIS PENA
Dr. Pena is a physician, forensic examiner, position of deputy with the LA County Coroner. Describes his duties as a coroner. Determines cause of death and manner of death, whether the death is natural, accident, suicide undetermined or homicide. Explains the autopsy photos. Photographing the decedent can occur at all phases of the autopsy. Their case number is included in all the photographs they take. Explains the documentation of the injuries of the bodies. 2008-2159.
Typical for detectives to be present. Richard Lewis. Sgt. Herman, from Santa Monica PD. Height and weight. At the time of her death, Juliana was 5’7” and weighed 110 lbs. Cause: Strangulation. Manner: Homicide.
Dr. Pena explains the neck compression, manual strangulation, hanging, and ligature. types of strangulation. This is a manual strangulation, based on his experience. She had numerous abrasions above her voice box area. Petechia was present in the eyes. Numerous petechia. Neck compression blocks the blood flow, from the brain returning to the heart, and that’s what causes the petechia.
Standard autopsy diagram form of upper head front and side.
Bruises on the left forehead. Purple, red, means that the time that these bruises were placed there, her heart was still beating. Explains abrasions and the difference between bruises. Referring to the upper left face. Had abrasions around the eyes. Abrasions on left and right side of the face. There were abrasions on the right side of the scalp. The frenulum was torn.
Side view of Juliana’s head. Her face had a purple discoloration, but not easy to see in the photograph. The injury to the left eye was from blunt force. It wasn’t from strangulation. Never going to get that from strangulation. Next photo. This is the lower part of her eyelid, right side, showing the petechia. Next autopsy diagram of the neck area.
Injuries indicate that Juliana was scratching, trying to get the pressure off her neck. Dr. Pena continues to explain the injuries to the underlying structure of her neck. Explains how they know there was no instrument, ligature. Her hyloid bone was broken. The hyloid bone function is to stabilize the base of the tongue so we can speak.
The hyloid bone does not fracture easily. In older women, it calcifies easier, breaks easier. Ms. Redding was 21, it’s still developing. Her hyloid bone is still cartilaginous, so it’s going to take more force to break the bone. There was blood around the fracture. It tells us there was a neck compression event. It’s a marker. Dr. Pena’s opinion is that it was manual, to break it. If there was a ligature, there would have been markings on the external surface of the neck.
Difficult to determine the amount of pressure needed to create these injuries. Breathing will get harder, and a some point you will lose consciousness. Can’t tell how long it takes for the person to become unconscious. There is a window period, to resuscitate person, but after that, there’s brain damage.
On her tongue, there was a large bruise on the right side that went from the top side of the tongue to the underside. She probably bit on the tongue. Could be attributed to seizure, but the biting of the tongue is more likely.
Dr. Pena goes over all the injuries to Juliana’s head. New diagram, skull diagram. There were hemorrhages present on the skull, so she had blunt force trauma to her skull. Photo of the back of the head, her scalp pulled back and you can see the injuries.
All the injuries on Juliana’s head, could not be caused by a single hit. All the head injuries occurred prior to death. Other parts of her body sustained injuries. Another diagram, #20. Front and back of the body. Besides injuries to her head, face and neck, Juliana had injuries to her legs, lower back, her heels, upper back and a few other areas.
Juliana had injuries to her elbows, which Dr. Pena said is a difficult area to get injuries to. Feels the injuries to her back are from punches. Injuries to her foot could be from dragging on a carpet surface.
Diagram 21 side views sketch of injuries to her body. People’s 83, photos of Juliana’s back. Points out areas of lividity and where the deep bruising was found on her back. Confirmed through incision that the areas of the back had deep bruising.
Photo of the right side of her body, hip and thigh area injuries. Photo of her legs and injuries to her knees and the deep cut to her right leg near the tibia. Close up photo of her knees and the abrasions and contusions.
There are two long red lines right along the tibia of her lower right leg. Those are vertically oriented, red abrasions. People’s 40, the injury to right heel. There is a cut on the heel.
Diagram on the screen showing injuries to Juliana’s hands. Photos of the left hand. The acrylic is cracked on the ring and little fingers of the left hand. Photo of right hand. There is no nail on the right thumb. Another photo of the right hand.
Performed a sexual assault examination. There was no evidence of sexual assault. Injuries are consistent with manual strangulation and is evident in this case.
NO CROSS EXAMINATION
19. FELICIA BURKE
DIRECT EXAMINATION CONTINUES
Briefly explains how DNA testing is performed at Orange County Crime Lab. Pieces of evidence, the underwear, are up on the screen that she examined. She did a presumptive test for semen. She explains how that test is performed. Did not find any spermatozoa. When there’s no spermatozoa, they test for P30, that was also negative. Semen was not detected on the underwear.
Also examined the victim's tank top. Examined it for the presence of body fluids, specifically looking for semen. Like the underwear, also examined the tank top with an alternate light source. Refers to her notes for the results of her testing. Identified 10 areas for further testing. One area on the top was initially positive for semen. Did not see spermatozoa. Then looked for P30, that test was negative, which means she did not detect semen on the tank top.
Also received sexual assault kit and what it contained. Goes into detail as to the DNA extraction process with the items found in the sexual assault kit. Put several items forward for DNA extraction: Oral swab, two neck swabs, external genital swab, and anal swab for further testing. She did the extraction process for the neck swabs. Then the items are placed on a quantitation batch. Also extracted the right and left wet nipple swabs. Also extracted some fingernail scrapings and clippings. All of the information is captured in their information management system. Management and DNA system is where the results were stored and managed. That was the end of her job with this evidence at that time.
Examined other items, gold chain, Oxyclean bottle. She examined at least fifteen to 20 items. Some of the items are examined just for stain, to determine if they are blood or not, specifically dark stains. Not all are tested for sperm. Also examined contact DNA swab from a cell phone. Identifies envelope that has the cell phone. Her initials are on the envelope and tag.
Opens the envelope that contains the cell phone DNA swabs. Quantitation is the next step that determines how much DNA is present in the sample.
They often triage the items in a case, and prioritize those items that might yield good results from the start. Generally, infrequently test hair. First a trace examiner will examine the hair to see if there is a root that is sufficient for DNA typing. Generally, they are not the first items they would choose.
When they are finished testing an item, they generally send it back to the originating agency. Sometimes they have defense requests to examine evidence.
Noted there was a positive amylase samples for the vaginal, anal, and rectal samples. She prepared a typed report. She reviews her report. She reads from the report that there were not significant levels of amylase in those areas. Doesn’t mean there were none.
She collected 15 hairs from the underwear. She collected fibers, items from the tank top. A brown fiber from the tank top. 34 hairs from the tank top. Something from the bag that contained the tank top, and placed that in evidence.
To her knowledge, no fibers or hairs collected from Juliana’s clothing were tested. Fingernail scrapings were tested. Round table discussion with detectives. Met with detectives when they dropped off the evidence initially. There was another discussion with detectives but she doesn’t remember who was present.
It would not be uncommon to find hair in underwear.
21 ANNETTE MCCALL
Forensic scientist at Orange County Crime Lab since 1998. Explains her job and her CV and on the job training. Lists her memberships in forensics organizations. The Orange County Crime Lab is accredited. To get that accreditation, they are reviewed by the American Society of Crime Lab Directors, (ASCLD). As a DNA analyst, she is subjected to two annual proficiency testing exams a year, as well as one other testing.
Explains where DNA comes from and that it’s unique for each person except for identical twins. Explains what type of body fluids can contain DNA. They perform PCR type testing at the lab.
A loci is the plural of locus. A locus, is the location on the chromosome. An allele, is just a sequence of DNA. A profile is, several specifically chosen loci, put together. In 2008, they used ProfilerPlus kit, which looks for 9 loci, and two other testing kits. Explains what a testing kit is.
All the forensic labs use the same loci. They look for the same DNA sequences. CoFiler system looks for 4 additional loci. Also contains some of the same as IdentiFiler, that looks for 15 locations. Now, the lab just uses IdentiFiler, instead of the other two tests. IdentiFiler looks for all 15 loci in one test.
Recently used IdentiFiler to retest some of the items in this case. Neck swab, exterior of tank top front and back, and right front stove knob.
IdentiFiler gives us those two additional loci. The 15 loci were picked out by a committee by the FBI. These locations have high variations between people.
Met with detectives to discuss the items to be tested. Originally got some limited results, and then discussed the most efficient way to test these evidence items. Ms. Burke was the first person on this case. She took over the testing parts that Ms. Burke wasn’t trained in.
A shedder is someone who leaves a lot of DNA behind on whatever they may touch. People don’t always leave DNA behind when they touch something.
A single source profile comes from only one person. A profile with more than one individual is called a mixture. A major contributor is someone who left more DNA in the mixture. Mixtures are determined by the peaks that are present in the analysis report. Major contributors will have taller peaks in the report.
For every part of DNA testing there is a positive and negative control. A positive control is known DNA. Negative control, you expect to see no DNA. If they find DNA when they should have none, then they would know that there was a contamination. Witness explains about elimination and non elimination of profiles.
Population frequency estimate, is based on population data. The method they use to calculate is also used by other labs. Her documentation of her work is made at the same time that she examines the evidence.
She examined around 50 items of evidence, and around 40 reference standards. This is a lot of examinations.
Describe the amplification, molecular copying process. Going to copy the DNA millions of times to detect it. The machine does that. Once that is done, it’s placed on the DNA typing instrument.
Determined that neck swab was a profile of at least two individuals. Juliana could not be excluded as the major contributor, and that the minor contributor was from a female.
Interpreted the vaginal and anal profiles from the sexual assault kit. Juliana could not be excluded as the profile. DNA from her fingernails, only one source of DNA. Only one profile from sexual assault kit swabs. Opened the sexual assault kit once.
Swabs from the nipples, sent those for extraction and forward for testing. Obtained DNA profiles from left and right nipple swabs. There was a mixture from at least two individuals. One was a male, Brian Van Holt could not be excluded as a major contributor of the nipple swabs. I determined that the source of the DNA “probably weren’t saliva.”
Explains transfer and how it can happen. You touch an item, or someone comes along and touches an item you’ve touched, and transfers your DNA.
DNA diminishes after time. There isn’t a particular time frame that DNA degrades. The hotter it gets, it will degrade faster. Washing can diminish DNA. Can’t say specifically how much has to be left, to be transferred. Studies have been done on transfer DNA. There are different studies that have different conclusions as to transfer. Some have good conclusions, and some have not.
Presents tank top to jury. When she received the tank top, she took two swabs and ran it along the length of the tank top. From the front and back of tank top, received mixtures from two individuals. Major contributor Juliana Redding could not be excluded. The other DNA profile was from a female.
Conclusion of the neck swabs, there was a minor DNA female profile. The neck swabs and the unknown female profile on the tank top were consistent with each other.
Performed DNA typing on the cell phone. Did the ProfilerPlus amplification and testing. For this item, she didn’t handle the swabs, she just put the extraction through the system. Her conclusion was there was a mixture from at least two females. Juliana Redding could not be excluded. The major female profile, was consistent with the unknown profile from the neck and tank top. ProFiler and CoFiler were the test kits she used.
Tested the DNA swabs from the stove knob. There was a mixture of two DNA profiles. Juliana could not be excluded as the major contributor, and the minor contributor matched the other tested items At the time she tested the items, she did not have a known profile from someone to identify the minority profile. She had excluded all the females that had been tested through this point.
Later she received additional items. She tested for blood on a latent print card. And evidence from a vehicle. Between 2008 to 2012 for all the items was when she tested them.
She came up with a DNA profile from the blood drop on the latent print card in March 2009. She observed a possible apparent blood. She pulled back the tape and tested it for blood. That was positive. She has experience with latent prints and would be able to tell if the tape on the fingerprint had been pulled back prior to her doing so for testing. She amplified and tested the blood on the card. Ran DNA testing on the blood This was a single source profile. Did not get any indication there was a second profile in this sample.
It was round and circular stain. A transfer stain, would be more of a swipe verses a round drop. That profile, did not match any of the comparison DNA’s that she had previously. The profile of the blood stain, was consistent with the profile of the other items she tested.
She received a reference sample in July 2010 of Kelly Park. Came up with a profile. Compared it to the previous samples obtained. Compared it to the blood stain. Kelly Park could not be excluded from the source. Came up with a frequency estimate, based on her findings. Based on population frequency estimates.
Blood on the latent print card: The frequency of choosing at random, on latent print card is more than 1 in one-trillion. The lowest average of all the things we’re looking at. Compared profile of Park to cell phone. Park could not be excluded. Frequency is more rare than one in one-trillion.
Compared profile of Park to the right stove knob. Park could not be excluded as the minor contributor. Frequency is more rare than one in 20 thousand. Compared Park to the tank top. Park could not be excluded as the minor contributor from the back and front of the tank top. Frequency is more rare than one in 200 (million) individuals. Neck swab. Kelly Park could not be excluded as a minor contributor from the neck swab. Frequency more rare than 1 in 300 million. Compared Park to the interior front door handle swab. Park could not be excluded. Frequency rarer than one in one-trillion. Profile of minor contributor could not be determined. There was too little DNA to develop a profile.
She tested somewhere between 40-50 other items of evidence. Tested approximately 40 individuals. Blood drop or saliva from mouth is a direct sample. Secondary samples are from items. Other items she tested, she only found Juliana Redding. There were items she tested where a full profile could not be obtained.
Fingerprints are unique to individuals. Twins would not have the same fingerprints. The latent print card was a typical latent print card. It did not appear to be disturbed when she received it for testing.
McCall describes the DNA collection and processing procedures in more detail. They first put the item in a small tube with a reagent to break open the cells. Explains what a reagent is. Explains what a nucleus is. DNA is released from the nucleus and put in a smaller volume of liquid. They concentrate it down to 10 micro liters. less than a drop. That process is extraction. Quantitation is the next step which takes about a micro liter of that drop. That is put in with reagents, that look for a particular location on the DNA to determine how much of the DNA we have.
Amplification, is the molecular copying process. The analysts use commercially sold kits to target the location on the DNA, on the specific loci of the DNA molecule. The amplification process just copies the DNA at specific loci and puts a dye on the molecules. Explains that process of putting the dye on the molecules.
Scientists call their machines, instruments. Explains what the instruments do, and the reports that are generated. Electropherogram is a graph with a peak onto it. It comes with a couple of numbers. One identifies the allele, and the strength of the allele, or the “height” of the peak.
You can end up with no result, a single person result, or a result with more than one person. If there are three or more peaks at one or more loci, they know they have a mixture. Different people can have the same genetic markers at some spots, but unless they are identical twins, they won’t have the same markers at all the loci. Uses the example of a phone number that many numbers could be made from the phone number. When a peak is taller, it means it has more of that allele, than that of the smaller peak.
DNA analysts can’t say for certain that someone is a contributor. They can say they are a possible contributor.
Witness is asked about transfer. Cells on the surface of the skin, do not contain a nucleus. Might find the DNA of someone who touched an object, or might not find any of someone who touched an object. With sneezing, drinking from a glass or sweating, they leave a huge amount of DNA behind. If you use towel in bathroom, that could leave DNA behind. However, analysts don’t know how much. It's possible that someone could come along, and get that person’s cells on their hands. Or they could use that towel, to wipe an object, and the DNA could get on that object.
There’s different types of transfer. Primary transfer, secondary transfer, and tertiary transfer.
Transfer is possible. It’s also depends on how much DNA is on an individuals own hands. Analysts can not tell how that DNA got there. they can’t tell if it came from primary or secondary. Possibly tertiary, but would not make a determination. Analysts can not tell how long cells from DNA have been on an object. The witness states she would not be comfortable rendering an opinion.
There is a threshold when they analyze their DNA. It’s 100 RU’s. It represents the strength of the DNA. Sometimes they see peaks, that are between 50 and 100. They could be real alleles, but they cannot be confident in reporting. They could be, bu they can’t be confident of the DNA.
Swabs from Redding’s neck. Ms. Park can’t be excluded as the minor. The defense asks about the test on the neck, and if the witness found alleles, on the neck, that tested over 100, that are not matched to Ms. Redding or Ms. Park.
On the neck swab there is a number 17. Park and Redding do not have a number 17 on locus D3. There were other numbers, below the threshold that do not come from Park or Redding. At locus D13, there are two low number 12's. On locus D7, there is a number 10 that is low.
In the later testing, in August 2010. There were other alleles that were below the 100 number threshold but above 50. DNA from at least one other that was in the sample, if those alleles are, in fact, DNA. Questions about the right front stove knob DNA results. More alleles that are two low to be included. There are three low peak alleles on three different locus that did not belong to Park of Redding. If in fact, those are true alleles. The source of the DNA on the stove knob was not known, just knew that it was DNA. Concentration similar to Ms. Park on the stove knob, was weak. There is no male DNA found on the stove knob.
The tank top (back?). When tested sample with ProFiler plus kit, there are three locations that are below threshold, but above 50. Three alleles at three loci that did not come from Redding or Park. (If in fact, they are true alleles.)
Swab on the front tank top. Did not find any below threshold in IdentiFiler, that doesn’t account for Park or Redding. In the other testing, she has 16/17 at one loci, and that’s below threshold. In ProPlus at one loci, has a 12 allele, that isn’t either Park or Redding Another allele, that is not Park or Redding, but above 50.
Swab of back of tank top. One allele in ProfilerPlus that was not Park or Redding. That was allele 12 at locus D13. Other random alleles below threshold. D8 had a below threshold allele. 15, above 50
D21 had one as well. below threshold, but above 50. Had three alleles that did not come from Park or Redding. If the below threshold are true alleles.
The DNA found on the cell phone could not exclude Ms. Redding or Ms. Park. She cannot tell where on the cell phone the DNA was collected since she did not swab the cell phone. The amount of DNA found on the phone was about a milligram and a half of DNA. That is about, somewhere between 200 or 250 cells. 200-250 cells is enough to test.
The crime lab ran a reference sample of Ms. Brooks. Ms. Brooks did not match the samples from Ms. Redding's neck.
Frequency estimates questions. She looks at all the alleles of all the known (contributors).
Question about a specific loci and if a statistic was done on that loci. Question if they ran Ms. Redding's type at that loci. Witness states that’s not necessarily true. There’s a value for a major female, there, but Ms. Redding’s value was not entered there, no.
This process is used every day. During the testing process, if something goes wrong there are controls in the system, that alert them. In your, statistics, you state, that, the frequency of choosing this defendant, with this profile. However, the witness states this profile is more rare than one in one-trillion.
The cell phone. Where there is a mixture, the possibility of choosing someone at random, is one in one-trillion people. The frequency is more rare, than one in one-trillion for more than one contributor.
That profile was present on several items. Consistent with profile on cell phone, the front and back of tank top, the neck, the front stove knob, and interior of front door. She found the profile on six items/locations.
You testified, that under the right circumstances, DNA can last forever, and that if kept in a freezer, DNA can last until a later date. Court asks a question about what "controlled environment" means.
Questions about how long DNA would last on several different surfaces.
The environment of a tank top being worn: It just depends on if it’s kept in a cool dry area, then it could be on there for a while. The environment of a door handle: It depends on where the door is, and how many people would have access to it. The environment of the neck area of a body: DNA would not keep or last for a long period of time.
Explains the threshold for determining DNA. Threshold under 100, it’s possible it could be an allele, but it could also be something else as well. Threshold alleles, over 100, could those be the result of transfer. That’s possible as well.
Firefighter would not leave DNA on stove knob if he was wearing gloves and there was no DNA on the exterior of the glove. Asked about the random allele that met the threshold on the neck, that did not belong to Redding or Park.
Going over loci VWA, and the extra allele there is a 16/17. The 16 is below threshold, and the 17 is above threshold. Sometimes, when the peak is not sharp, they cannot be confident that it’s an allele.
Explains the different between ProFiler Plus and IdentiFiler. ProFiler Plus tests 9 loci; IdentiFiler test 15 loci.
Explains about the frequency calculations of a particular profile, and other threshold standards that are used to include an allele grouping.
Is it not uncommon to have another person’s allele on you at a low threshold. It is not uncommon to find low level DNA on a person.
She tested several reference samples and secondary reference samples. For a loci that had numbers that did not belong to Park or Redding, Ms. Rutledge had a 17 for that loci and Ms. Brooks had a 16 at that location.
Explains the big chart, 'Report of Evidence Examination and DNA Typing' and how the chart is read.
If possible, a reference sample matches an evidence sample in one allele at one loci, analysts can’t determine anything. They would need to see more of that DNA throughout the profile.
Loci D3 is on that chart (possibly prepared by DA's office) but it’s not labeled correctly. Prosecution exhibit 102 fails to accurately list loci D3 data on it.
To be continued in Part II, Final Witnesses...