F19 10 DNA Forensics Procedures - Assignment PDF

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DNA Forensics Lab Procedures and Assignment Learning Goals: • To learn and explore the process of forensic analysis • To learn and explore DNA properties and DNA analysis • To learn how to isolate DNA from cells PAGE Crime Laboratory – Case File: 115078…………………………………………………………………….….1 Part I: Forensic Analysis Activity 1. Hair Analysis………………………………………………………………………….………4 Activity 2. Pollen Grain Analysis……………………………………………………………………..5 Activity 3. DNA Analysis………………………………………………………………………….….…..6 Part II: DNA Isolation Activity 4. Isolation of Cheek Cell DNA……………………………………………………………8 Concept Questions……………………………………………………………………………………………….…….9 Assignment……………………………………………………………………………………………………….….…..10

Case File: 115078 Defendants: Dennis Williams and Kenny Adams Case Opened: May, 11 1978 Case Closed: February 6, 1979 Case Summary:

Date of Crime: Convicted of: Death-qualifying factors: Trial History: Date Sentenced Defendant’s age at crime Defendant’s sex Victims: Age of Victim: Relationship of victim to defendant Trial Judge: Prosecutors: Defendant’s plea: Was guilt phase bench or jury? Was sentencing bench or jury?

May 11, 1978 Kidnapping, armed robbery and murder Murder and murder committed in the course of another felony Convicted in 1978 and after reversal of the initial conviction, again in 1987 February 6, 1979, first trial; March 1987 second trial 21------- born February 13, 1957 Male John Lionberg and Carol Schmal 29 and 23 none Dwight McKay, first trial; Frank Meekins, second trial Clifford Johnson and J. Scott Arthur, first trial; J. Scot Arthur and Deborah Dooling, second trial Not Guilty at both trials Jury at both trials Jury at first, judge at second 1

Summary of state’s theory of case at trial:

Summary of defense: Did the defendant confess or make and inculpatory statement? Did the defendant testify at trial? Was there an eye-witness?

Was there serological evidence?

Was their hair or fiber evidence? Was there any other evidence?

Was there informant testimony?

Sometime after 2:30 am, Carol Schmal, who had just become engaged, was abducted along with her fiancé, John Lionberg, from a gas station near Homewood, Illinois and taken by Williams and codefendants Kenneth Adams, Willie Rainge and Verneal Jimerson, to an abandoned townhouse in East Chicago Heights where Lionberg and Schmal were shot to death. Williams, Adams and Rainge were tried together in 1978. Williams was sentenced to death, Adams and Rainge to long prison terms. For reasons explained below, Jimerson was not tried until 1985. He, like Williams, was sentenced to death. The convictions of Williams and Rainge were reversed in 1982, but they were tried again and convicted in 1987. Williams was again sentenced to death, Rainge to prison. Mistaken identity, absolute actual innocence no no At the 1978 trial, Charles McCraney, who lived near the murder scene, testified that Williams and the two co-defendants had been in and around the abandoned townhouse about the time of the crime. At the 1987 trial, McCraney again so testified, but he was joined by Paula Gray, a 17-year-old friend of the defendants who claimed that she witnessed the murders by the defendants. Yes. Blood not belonging to the victim was found on the scene. At the 1978 trials, state serologist Michale Podlecki testified that at least one of the murderers had a type of blood found only in 25% of the population and that both Williams and Adams shared this blood type. Before the second trial, re-testing of the blood evidence by an independent consultant established that Podlecki’s original testimony had been incorrect and that Williams actually did not share the blood type with evidence found at the scene. DNA fingerprinting was not available at the time of either trial. Yes. Several hairs were recovered from the scene and do not match those of the victims. Yes. Pollen grains were recovered from the scene of the crime and from soil taken from the suspects’ shoes. Yes. David Jackson, facing burglary charges, testified at the trial that he had been in a cell with Williams and Rainge shortly after their arrest. Jackson claimed that he overheard Williams and Rainge talking about killing a woman and her boyfriend the night before. Jackson quoted Williams as saying, “ They will never find the pistol, you know. We ain’t got nothing to 2

Did the informant receive anything of value for testifying?

Was there accomplice testimony?

Was there a Brady issue?

Principal exculpatory evidence at trial:

Evidence introduced in mitigation:

worry about”. Jackson did not testify at the second trial. Yes. On October 11, 1994, Jackson recanted saying he had fabricated his 1978 testimony “because I was offered a deal” by Assistant State’s Attorney Clifford Johnson and J. Scott Arthur. In return for his false testimony, said Jackson’s affidavit, Johnson “put me in protective custody and had me flown to Minneapolis, Minnesota about five days after trial. I stayed there about 6 years before returning home.” Not at the first trial, but at the second. Following interrogation spanning more than 2 days in two motels in May of 1978, Paula Gray gave Cook County Sheriff’s police a statement saying she had been present during the murders. Before the first trial, she recanted, whereupon prosecutors charged her with both the murders and perjury. She was convicted and sentenced to a total of 50 years in prison. Paula Gray was certified mentally incompetent. Yes. Following the 1978 trial, it was alleged that the state’s star witness, Charles McCraney, had made an initial statement to the sheriff’s police that had not been turned over to the defense as required by Brady vs. Maryland. However, the most significant Brady issue did not become known until 1996, and never was brought to the attention of the court. It was a report of an interview that Sheriff’s Officers Howard Vanick and David Capelli conducted with a witness who identified a different killer five days after the victims’ bodies had been found. The witness, Marvin Simpson, heard shots fired and saw Arthur Robinson and Jim Richards fleeing the murder scene. The report apparently had been turned over to the defense prior to William’s second trial, but, due to ineffective assistance of counsel; nothing had been done with it. It had apparently been withheld prior to the first trial, in violation of Brady Alibi witnesses testified at the 1978 trial that Williams, Rainge and Adams were elsewhere when the crime occurred. Rainge’s girlfriend testified he was with her at his home at the time of the crime. Adams’ mother testified that her son was at home asleep. Williams had no record of violence. He was a high school graduate.

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Lab Activities PART I: FORENSIC ANALYSIS Dennis Williams and Kenny Adams have been in jail, on death row, for 18 years for the murder of Carol Schmal and her fiance. You are a group of Northwestern University Students working on the Innocence Project. It is 1996. You are following up on an article written by Rob Warden, in 1986 (14 years earlier) and an 18 year old police file that calls into question the witness testimony at the trial. In this article titled “Will we execute an innocent man? Rob Warden reports on an eyewitness who, five days after the killings, identified two other suspects, Jim Richards and Arthur Robinson, as the murderers. Unfortunately, due to the passage of time, a conviction and unexpected advances in scientific analysis, you have an incomplete forensics data set. One suspect (Jim Richards) was not questioned until 14 years after the murder preventing the collection of trace evidence and another (Arthur Robinson) died prior to questioning preventing analysis of DNA samples without a court ordered exhumation. I. After petitioning the court, you have received permission to do forensic analyses on the evidence found at the crime scene. II. You have the evidence on your table. a. Hairs taken from the crime scene b. Pollen grains collected from the crime scene and dirt from the suspect’s shoes. c. DNA evidence from the victims and an unknown sample that is likely to be the murderer. III. Your job is to re-evaluate the evidence using tools either not available, or not widely accepted in 1978 to determine if Dennis Williams has been wrongfully convicted.

Activity 1. Hair Analysis: Hair analysis is a universal technique in forensic investigation and can give useful information on a number of different aspects from the ability to identify an individual to whether a person has used drugs. The identification and comparison of human and animal hairs can be useful in demonstrating physical contact between a suspect and a crime scene. Hair can be used to rule out certain suspects or scenarios. It can also be used to corroborate other physical evidence if it is consistent with the rest of the evidence. Hair can be examined microscopically to reveal characteristics of its physical structure. Hair is composed of three principle parts: Cuticle - outer coating composed of overlapping scales. The scales may vary in how many there are, how much they overlap, their shape and how much they stick out from the surface. Medulla - central core, which may be absent. The medulla may vary in thickness, continuity (i.e., may be broken into pieces) and opacity (how much light is able to pass through it). Cortex – protein rich structure surrounding the medulla; contains pigment. The cortex varies in thickness, texture and color and distribution of pigments. The cortex is an important component in determining from which individual a human hair may have come.

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You have four samples of hair on the slides at your table. Unfortunately, with the crime being investigated, some forensic evidence has been lost or destroyed. Examine the characteristics above and determine if you can rule out or support any particular suspects. Use the table below to record your data.

Hair Sample Carol Schmal (V) Kenny Adams (K) Dennis Williams (D) Unknown sample from crime scene (T) Jim Richards (J)

Notes

Activity 2. Pollen Grain Analysis: Forensic researchers regularly analyses pollen on the jeans, shirts, and hairs of a victim or suspect to indicate whether a victim or offender had been in a place where the particulate plant matter occurs. There exist several pollen reference databases that can help the forensic scientist with identifying a particular species thus regionalizing their location during criminal investigation. It is possible to identify to genus, and in some cases to species, the plant that a pollen grain came from. Palynology or the study of pollen grains is increasingly being used in forensic analysis and has resulted in multiple convictions based on the power of this evidence. As you can see in this figure, the wide variety of pollen grain morphology, combined with the limited distribution of certain plants, can pinpoint the location that trace evidence originated from.

The murders took place in the winter in Chicago, so there were few plants in flower and the ground was covered in snow. The murders took place in a garden shed at a vacant townhome, 5

with a preponderance of cultivated ornamental plants nearby. You have slides of pollen on the table. One sample was collected at the murder scene. Two additional samples were retrieved from soil removed from each of the suspect’s shoes. Look at each of the pollen grains slides on your table. Take particular note of the shape, size and type of ornamentation on the surface of the pollen grain. Can you definitively place either of the convicted murderers at the scene of the murder? Pollen Grain Sample Background Pollen from crime scene (TP CS) Pollen from soil removed from Dennis Williams’ shoes (TP D) Pollen from soil removed from Kenny Adams’ shoes (TP K)

Notes

Activity 3. Forensic Analysis of DNA: If necessary, review your background packet on information about DNA forensics and electrophoresis.

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At this point, you may have excluded certain suspects, or not. Use the evidence you have collected so far to identify two individuals that you think may be the murderers. Each team of two students may choose two suspects to analyze DNA profiles. Available at the TA desk are DNA samples taken from the crime scene (victim DNA , V; and trace DNA, T) not belong to the victim) and from each of the suspects: Arthur Robinson (A), Dennis Williams (D), Jim Richards (J) and Kenny Adams (K). You will select your two most likely suspects and analyze their DNA to find the killer. Is it Dennis Williams who several eyewitnesses testified that he was not only at the scene of the crime, but bragged about it to his buddies? Or is it Jim Richards and Arthur Robinson for whom only a single eyewitness has identified as the killers? The tubes at the desk contain DNA samples (25 µl) from each of the individuals described above that have each been digested with restriction enzyme Eco RI. Once you have selected your samples, you will watch TA do the following. 1) Wear gloves and eyewear protection. 2) Place DNA samples in the 37°C water bath for exactly 5 minutes. 3) Use the pipette at the table to add 2 µl of the blue loading dye to your 25-µl sample. This dye will stop the enzymatic reaction, make it easier to see the DNA sample as being loaded, and also contain glycerol which will cause the DNA sample to sink to the bottom of the well. 4) Load 25-µl of each DNA sample; DNA of the victim, trace DNA from the crime science and DNA from the suspects, onto the gel. TA will load the gel with: 1. DNA collected from the victim (V) 2. Trace DNA collected at the crime scene (T) 3. Arthur Robinson’s DNA (A) 4. Dennis William’s DNA (D) 5. Jim Richards’s DNA (J) 6. Kenny Adams’ DNA (K) 5) TA will place the lid tightly on the electrodes. 6) The gel will be run at 145 V for 45 minutes. 7) When the gel has finished, TA will place the gel in a box with stain for 10-15 minutes, then into distilled water (in a Carboy) for 3 x 10 min. This will take out the stain that hasn’t bound to the DNA so that the DNA fragments can be visible better. While the gel is being stained and destained, you will do the following exercise in PART II. 8) After destaining, place the gel box on a white piece of paper and analyze the results. Remember that restriction enzymes will always cut a specific DNA the same way every time. So you can compare the sizes of bands in the trace evidence collected at the scene to (1) rule out the victim’s DNA, and (2) identify the suspect(s) who was/were present at the crime scene. Draw the results of the DNA profile from the DNA gel electrophoresis results. Discuss as a class what the results mean.

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PART II: DNA ISOLATION DNA-the seemingly mysterious substance that holds the secrets of life, turns out to be a relatively simple chemical polymer made of repeating patterns of A’s, T’s, C’s, & G’s (representing the chemicals Adenine, Thymine, Cytosine, & Guanine). How can something so simple be the very stuff of life itself, the instruction booklet for life, a how-to guide for building a living thing? This lab will de-mystify DNA by allowing you to see it for your own eyes as a rather abundant substance found in virtually all of your body’s cells. Students have to wear gloves and eyewear protection while isolating cheek cell DNA.

Activity 4: Isolation of Cheek Cell DNA Protocol: 1. Take a cup of Gatorade from the TA desk. 2. Put the Gatorade in your mouth and swish it around, occasionally using your teeth to scrape (gently!) the sides of inside your mouth. Do this for exactly 1 minute. 3. Spit the Gatorade back into your cup. 4. Pour your Gatorade (with cheek cells!) into a 15-ml tube. 5. Add 2 ml of the lysis solution. (Remember what was in here? And why it was there?) 6. Gently invert your tube 5 times. Exactly 5 times. 7. Let sit undisturbed for 2 minutes. (What is happening right now? Why wait?) 8. Add ice-cold isopropanol up to a TOTAL volume of 13 ml in your tube. Your TA will demonstrate how to do this. 9. DO NOT DISTURB YOUR TUBE. Let it rest and so the isopropanol can do its job. (By the way…what is the isopropanol doing? Why ice-cold?) Let it sit for 10 minutes. Check your gel progress while this is going on. 10. After 10 minutes, you should see some clumps of white DNA visible. 11. Using the plastic pipette, suck your DNA and put it into a microfuge tube. Add a piece of string if you like and you have a DNA necklace.

Understanding the concepts of DNA isolation protocol by answer the following questions: 1. What does the lysis solution do to the cell’s membranes?

2. How does the DNA lysate become visible?

3. Why can you see the extracted DNA without a microscope?

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Concept Questions 1. What role did each of the following people have in developing the information we now have about DNA? 1.1) Rosalind Franklin 1.2) James Watson 1.3) Francis Crick 2. What is the basic composition and structure of a strand of DNA? 3. How is DNA molecules packaged so that it fits onto the nucleus of a cell? 4. In the DNA extraction for your cheek cell, what is the purpose of each of the following solutions? 4.1) Sports drink 4.2) Lysis solution 4.3) Ice cold 70% isopropanol 5. What are restriction enzymes? What do they do? Where do they occur in nature? 6. What is DNA profiling? 7. What is the role of restriction enzymes in the DNA profiling procedure? 8. How was DNA profiling used in this lab?

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Assignment This lab is worth 10 points. Complete Part I in class. Hand in Part II next week. Part I (Work sheet) (5 pts) 2 points: Hair analysis A brief summary of analysis of the hair evidence. Write one paragraph with COMPLETE SENTENCES.

2 points: Pollen grain analysis A brief summary of analysis of the pollen grain evidence. Write one paragraph with COMPLETE SENTENCES.

1 point: Hypothesis and the sketched picture of the gel (draw the bands in the blank gel picture)

Part II (Report) (5 pts) Part II has to be typed (computer-generated) and printed. Hand-written report wil not be graded. Write complete sentences in a paragraph format. 2.5 points: Conclusions based on the DNA gel electrophoresis results as well as the hair and pollen grain evidence. 2.5 points: Accept or reject your hypothesis? Explain logically why based on all forensic evidences (hair, pollen grains, and DNA).

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