Summary of Thoughts: Prep: Clothing and safety requirements (goggles, lab coat/apron, pants, closed shoes) Bring the stuff you can bring especially notes Part A: Unknown Solids, Liquids and Metals Make flow charts (which tests tell you which cmpds you have) Study the possible combinations Part B: “Polymer” testing Know the hairs (both the appearance of the medulla inside and the scale pattern on the surface) Know the fibers (microscope image identification) Know the polymer density ranges and burn test results Part C: Paper Chromatography/Mass Spectrometry See the WSU SO website for my paper chromatography primer We will do Mass Spec on a drug sample this year (give mass spec, and 4 possible structures) Part D: Physical Evidence Fingerprints are a given Possible DNA chromatograms this year Blood spatters and shoe prints are a possibility as well Glass is a favorite of mine Part E: Crime Scene Analysis Leave time to write your essay Who and Why…..Who and Why Not Start to think: I KNOW that evidence X can be associated with person Y Neatness, grammar, spelling Clarity of thought (can I easily follow what you are doing) Correctness of associations (are you properly associating evidence X with person Y) Correctness of conclusions (are you properly interpreting your evidence and associations)

Science Crime Busters (SCB) & Forensics (FOR) 2011 Physical Science & Chemistry Both of these events are 5 part events: Qualitative analysis of unknown materials Polymer Testing Chromatography Crime Scene Evidence Analysis

Changes Note sheet clarified Safety clothing requirements Change in part b—water quality testing Removal of hairs and fibers from part d Tie breaker rule

Part 0: Being Prepared NOTE SHEET Equipment: Bring your kit. Bring everything allowed in your kit. Safety: Lab coat, apron or other type of front torso, leg and arm protection Eyewear: Science Olympiad is very clear that the team must wear Chemical/Splash resistant eyewear. Seal around the face, do not have direct vents. http://soinc.org/eye_protection Clothing: Closed toe shoes “Pants”: long skirts acceptable but not recommended, no capris Socks Covered arms (see above) NOTE SHEET www.soinc.org

Part 1: Qualitative Analysis In the past, this has been the worst performance section. For SCB this part is 50% of the score (only 20% for FOR). How to do it: Knowing what is in your kit, how to use it and what it tells you is very important. Get all the things and have them. That includes your note sheet. SCB mixtures: use a magnifying glass at first to try to visually test. Many of the substances are translucentcrystals, seeing dissolution on a white plate is very hard. Try to acquire clear plastic or glass dished for your teams to work with. http://sciencekit.com/plates-and%23038%3B-spot-plates/c/3286/

Part 1: Qualitative Analysis How to prepare: Method 1: Obtain all the potential chemicals form the list, use every technique available on each chemical and record the results. This can be a brute force table approach or be incorporates into a flow chart. Method 2: “Steal” a flow chart from the internet. Neither of these substitutes for the experience of seeing and interpreting the results that comes from practice.

Part 1: Qualitative Analysis Resources: Sciencekit.com and other supply houses sell chemicals and equipment, WSU, your local university or high school science department. Study materials on how to do tests: FOR--http://soinc.org/sites/default/files/uploaded_files/qualhints.pdf http://soinc.org/sites/default/files/uploaded_files/forensics/For_ForensicsQualReactions.pdf SCB-- http://soinc.org/sites/default/files/uploaded_files/crimebusters/Individual%20Solid_Nonmetal_analysis.pdf http://soinc.org/sites/default/files/uploaded_files/crimebusters/Liquid_analysis.pdf

Part 2: Polymer Testing Hair identification: SCB: human, cat, dog FOR: bat, horse Hairs presented as images; Know scales and medullas Fiber identification: SCB: animal, vegetable, synthetic FOR: cotton, wool, silk, linen, spandex, polyester Samples presented as images and pieces of fabric; Microscopic appearance (how they burn for FOR) Polymer identification: SCB: PETE, HDPE, PS, LDPE, PP, PVC FOR: PC, PMMA Samples likely presented in text format; Know density ranges and burn test results

Part 3: Paper Chromatography This is a relatively simple experiment to perform and interpret, yet is still the second most poorly performed section. However, it is not the most highly weighted experiment. How to do it: Lets give it a try. This is also about visual and quantitative comparison of the spots that are observed. SCB—you will do strict visual comparison of the patterns/colors obtained form the test. FOR—you may be asked to include calculations of retention factors to “prove your point” (spot distance/solvent distance)

Part 3: Paper Chromatography How to prepare: http://www.yesmag.ca/projects/paper_chroma.html http://soinc.org/sites/default/files/uploaded_files/forensics/For_Chromatography2.pdf Get some paper towels, filter paper, coffee filters, absorbent art paper, something that is going to wick water via capillary action. Get cups, beakers Get pens (not gel pens), water color paints, M&Ms, Kool-aid and do it.

Part 4: Physical Evidence Many possibilities: Blood spatter evidence Fingerprints Shoe/tires DNA Glass Entomology Seeds/pollen Blood type Bullet striations

Part 4: Physical Evidence Fingerprints: 3 pattern types (arch, loop, whorl) SCB Each has subtypes FOR Plain arch, tented arch Ulnar loop, radial loop Plain whorl, central pocket loop whorl, double loop whorl, accidental whorl Identify deltas, identify ridge flow Types of minutiae points Types of development

Part 4: Physical Evidence Blood stains Blood stains identify their direction of travel Round/circular stains landed perpendicular to the surface Oval stains have a tail that points in their direction of travel, opposite their point of origin (asin Θ = W/L) Size is relative to force (velocity)

Part 4: Physical Evidence DNA Students must be able to interpret DNA separations to determine possible donors FOR students need to be able to discuss the PCR process Shoe/Tire Students must be able to match shoe and tire tracks based on pattern comparison and individual characteristics

Part 4: Physical Evidence FOR Event only Seeds/Pollen Just need to look at pictures, visual comparisons Soil Wet and dry color comparison if allowed Bullet striations Just need to look at them again ABO blood typing Conceptually is very easy to accomplish with a few materials, we may do this this year Additionally, there is a place for blood cell species id based on visuals

Part 4: Physical Evidence Glass Refractive index is the amount that light bends, you can do numerical comparisons Glass fractures do not cross other glass fractures, tells you which crack was there first High impact in glass cones out the exit side Entomology Insect arrival ordering, http://www.clt.uwa.edu.au/__data/page/112507/fse07_forensic_entomology.pdf

Part 5: Analysis of the Crime Most important part of the whole event Need to leave plenty of time to write it up Who and WHY!!!! Who and WHY NOT!!!! Criminal justice is about proof, forensics is about identification and the strength of the association Developed a rubric to grade on: neatness, grammar, spelling, clarity of thought, correct associations, correct conclusions are all a part of the score. Practice two things: evidence X has this some level of significance; person Y because

Science is Fun… …but only if you know something. The students that enjoy the event the most and the ones that come prepared. Otherwise it is 50 minutes of frustration. Many of the activities in these events are qualitative and descriptive, but are also great ways of getting students to reason through the logical processes of scientific discovery (read: problem solving)