Write to a Fair Trial: Forensic Handwriting Analysis · 196.181022 Edvo-Kit #196. 196. Write to a...

196.181022

196Edvo-Kit #196

Write to a Fair Trial: Forensic Handwriting AnalysisExperiment Objective:

Your lab notebook has been stolen, replaced with a ransom note demanding lunch money in exchange for its safe return! In this hands-on experiment, students will use principles of forensic handwriting analysis and paper chromatography to examine writing samples from 4 potential suspects. Only after careful analysis will they be able to solve the classroom crime.

See page 3 for storage instructions.

SAMPLE LITERATURE

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PageExperiment Components 3Experiment Requirements 3

Background Information 4

Experiment Procedures Experiment Overview 7 Module I: Handwriting Analysis of the Ransom Note 8 Module II: Paper Chromatography of Ink Samples 9 Study Questions 12

Instructor’s Guidelines Notes to the Instructor 13 Pre-Lab Preparations 14 Experiment Results & Analysis 15 Answers to Study Questions 16

Appendix A - Suspect Handwriting Samples and Ransom Note 17

Safety Data Sheets can be found on our website: www.edvotek.com/safety-data-sheets

EDVOTEK , The Biotechnology Education Company, and InstaStain are registered trademarks of EDVOTEK, Inc.

Table of Contents

Write to a Fair Trial: Forensic Handwriting Analysis EDVO-Kit 196

1.800.EDVOTEK • Fax 202.370.1501 • [email protected] • www.edvotek.com

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Duplication of any part of this document is permitted for non-profit educational purposes only. Copyright © 2018 EDVOTEK, Inc., all rights reserved. 196.181022


Experiment Requirements (NOT included with this experiment)

• Metric rulers• Pencils• Beakers (400 ml or 1000 ml recommended)

Experiment Components

There is enough of each sample for

10 groups.

All experiment components are intended for educational research only. They are not to be used for diagnostic or drug purposes, nor administered to or consumed by humans or animals.

None of the experiment components are derived from human sources.

Write to a Fair Trial: Forensic Handwriting AnalysisEDVO-Kit 196

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Component Storage Check √

A “Suspect A” Ink sample Room Temperature q

B “Suspect B” Ink sample Room Temperature q

C “Suspect C” Ink sample Room Temperature q

D “Suspect D” Ink sample Room Temperature q

E “Crime Scene” Ink sample Room Temperature q

• Handwriting samples (See Appendix A) Room Temperature q

• Chromatography filter paper Room Temperature q

• Mini transfer pipets Room Temperature q

Forensic handwriting analysis helps law enforcement officials, people in the court system, and historians identify the person responsible for a handwritten document. Forensic scientists analyze documents to check for signs of forgery, to see if any changes were made to a document after it was originally written, or simply to figure out who wrote or signed the document in the first place. They analyze historical writings, wills, autographs, or signed papers and handwritten notes left at a crime scene. When they make their reports, they call these papers “ques-tioned documents.”

Every questioned document is unique, so forensic scientists look at many different features of it during their investigation. Handwriting analysts examine the paper for clues about the motion, position, and pressure of the hand that wrote it, as well as the shape and spacing of the letters. This can tell them if the person wrote the note in a hurry or took their time, if they were old or young, and if they were sick or well among other things. The document can also be examined under a microscope or under infrared or ultraviolet light to look for cross-outs, additions, and tiny scratches on the paper that indicate the pen that was used. Finally, destructive methods can be used to reveal the chemistry, and occasionally even the age, of the ink.

To link a document to a specific person, the questioned document is compared to a confirmed sample of that person’s signature or handwriting. This could be a previously written document or handwriting samples obtained during an investigation.

Rather than look for similarities, however, examiners actually look for differences. If the two pieces of writing do not have differences, it is possible they are from the same writer.

Questioned document examiners look at four different aspects of handwriting (see Figure 1 for examples):

1. How the writer forms letters, including slants or slopes, letter sizes, tremors, or embellishments (fancy capital letters, different ways to cross the letter “T” or dot the letter “i”, or unusual shapes for letters that go below the line like “g” or “y”).

2. The appearance and direction of the lines, including ink smoothness, ink darkness, and whether the line is straight or waivers up or down. These indicate the pressure and speed of the writing.

Handwriting Analysis

Figure 1: Four different aspects of handwriting.



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3. Spacing between the letters and words and the spacing of the margins.

4. The content, including grammar, punctuation, phrasing, and spelling.

Requested samples are often written in front of an examiner. If handwriting examiners witness a sample being written, they can determine whether a person is making natural motions or whether they are making motions designed to disguise their normal handwriting.

Non-requested samples are taken from a writer’s home or office and include checks, lists, or notes. Even though the sample was done in private, an examiner can identify things that mean the writer was trying to disguise their handwriting, including shakiness in the writing, different thicknesses at the beginnings and ends of words, and un-natural spacing between letters.

Another form of handwriting analy-sis is called Graphology, and people who practice it claim that they can determine a person’s state of mind, mood, temperament, or compat-ibility with a second individual. Gra-phology is not supported by science.

Additional Ink-vestigations

Forensic scientists are also inter-ested in a document’s ink, which can come from a pen, marker, typewriter, or printer. The color and consistency of the ink can reveal the color, age and type of ink used. Infrared or ultraviolet light can reveal scratch marks or signs of previous writing on the document (Figure 2). In addition, checks and currency often employ infrared or ultraviolet reactive inks to prevent counterfeiting. Importantly, many of these methods are non-destructive to the original sample.

To further investigate the chemical formulation of the ink forensic scientists can extract samples of the ink from the document. Once collected, the ink is analyzed using a tech-nique known as chromatography, a type of chemical analysis that separates the components that make up a specific type of ink. These results can then be compared to samples in the United States Secret Service’s International Ink Library, which contains profiles of over 11,000 ink types. Often, this analysis will indicate the exact ink used in the document.

Chromatography separates mixtures according to their ability to dissolve in solutions and to stick to each other or a solid support. In paper chromatography, an absorbent cellulose fil-ter paper is used to bind the ink samples, which are then dis-solved in the solvent. The solvent moves slowly up the filter paper, carrying the dyes along. Importantly, the more soluble the ink components are in the solvent the faster they will migrate. This results in a gradient, with soluble components moving to the far end of the paper and less soluble components moving only a short distance (Figure 3).

Figure 2: Analysis of an altered check.

Figure 3: Chromatography

Origin

Solvent Front

More Soluble

Less Soluble

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Questioned document examiners usually possess a B.A. or have other advanced training, and must be tested to determine if they have excellent color perception and visual discrimination. Examiners may work for state or local police departments, or may be in private practice. The FBI itself has a Questioned Documents Unit that supports federal, state, and local police.

In this experiment, you will be an FBI Questioned Document Examiner who is assigned a ransom note from the horrible theft of a lab notebook from the classroom. Your task is to examine the note and compare the ink to that of pens found from four suspects. First, you will compare the handwriting in the note to the handwriting from the potential suspects. Next, you will perform a paper chromatography experiment to examine the ink used in the note and ink samples from the personal pens of each suspect. Together, the results from these analyses will pro-vide evidence that can be used to identify the thief and recover the stolen lab notebook.


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EXPERIMENT OBJECTIVE

Your lab notebook has been stolen, replaced with a ransom note demanding lunch money in exchange for its safe return! In this hands-on experiment, students will use principles of forensic handwriting analysis and paper chro-matography to examine writing samples from 4 potential suspects. Only after careful analysis will they be able to solve the classroom crime.

LABORATORY SAFETY

1. Gloves and goggles should be worn routinely as good laboratory practice.

2. Exercise extreme caution when working with equipment that is used in conjunction with the heating and/or melting of reagents.

3. DO NOT MOUTH PIPET REAGENTS - USE PIPET PUMPS.

4. Exercise caution when using any electrical equipment in the laboratory.

5. Always wash hands thoroughly with soap and water after handling reagents or biological materials in the laboratory.

LABORATORY NOTEBOOKS

Address and record the following in your laboratory notebook or on a sepa-rate worksheet.

Before starting the Experiment:

• Write a hypothesis that reflects the experiment. • Predict experimental outcomes.

During the Experiment:

• Record (draw) your observations, or photograph the results.

After the Experiment:

• Formulate an explanation from the results. • Determine what could be changed in the experiment if the experiment were repeated. • Write a hypothesis that would reflect this change.

Experiment Overview

Wear gloves and safety goggles

Handwriting Analysis of the Ransom Note – 30 min.

Module I

Paper Chromatography of Ink Samples – 45 min.

Module II


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Module I: Handwriting Analysis of the Ransom Note

Handwritten ransom notes are important pieces of evidence after the commission of a crime. There are many features in a person’s handwriting that can be examined to create a profile. For example, the size of the writing, both the height and width of the letters, can change significantly between individuals (see Figure 1). In addition, the spacing of letters in words or of the words themselves, the slope or slant of letters, and special characteristics (how a letter is dotted or unique flourishes) may help to identify an individual’s handwriting. In this module, you will examine writing samples from the ransom note and 4 suspects to help identify a potential culprit.

Handwriting Analysis

1. OBTAIN the writing samples from the 4 suspects. These can be found in Appendix A or as a separate printout from your instructor.

2. One at a time, OBSERVE the suspect writing samples, recording your observations in your laboratory notebook. In particular, pay attention to identifying characteristics within each handwriting sample, including:

• Size – Measure the height and width of specific letters in the handwriting. For example, use a ruler to measure the height of an uppercase “L”, or a lowercase “y” in each writing sample.

• Spacing – Use a ruler to measure the distance between letters or words.

• Slope – Draw a line through various letters to measure the slope. Do the individual letters slant to the left or the right? Are the sentences themselves level or do they slant up or down off of a straight line?

• Special characteristics – Are there any specific things in the writing that make is stand out? Are the lower-case “i” or “j” letters dotted in a special way? Are there any letters drawn in an unusual or distinguishing style, unique punctuation, or consistent spelling mistakes?

3. Once you have made observations for each suspect, OBTAIN a copy of the ransom note. Using the criteria that you established for the suspect handwriting samples, RECORD any defining features from the ransom note.

4. COMPARE the handwriting characteristics of the writing samples to the ransom note and identify a potential suspect for the crime. You are now ready to perform Module II: Paper Chromatography of Ink Samples.



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Module II: Paper Chromatography of Ink Samples

Paper chromatography is a simple and effective method to separate a complex mixture of dyes and reveal the in-dividual components. In this module you will use paper chromatography to separate ink samples from pens found in the possession of each suspect, as well as from ink extracted from the ransom note.

At the completion of the chromatography experiment you will calculate the retention factor, or Rf value for each dye. The Rf is calculated by measuring the distance traveled by the dye component and dividing by the distance traveled by the solvent. By calculating the Rf values for each component in the ink samples you will be able to identify which pen was used to create the ransom note.

1. COLLECT one paper chromatography sheet, one transfer pipet, and tubes containing the ink dye samples.2. Using a pencil and ruler, lightly DRAW a horizontal line across the paper chromatography sheet 1 cm from the

bottom. This is the sample origin line.3. Still using a pencil and ruler, DIVIDE the paper chromatography sheet into 5 equal columns by making small

vertical marks on the origin line. These will be a reference when loading the ink samples.4. PLACE the end of a transfer pipette into the crime scene (CS) sample. Very gently squeeze the pipette and

allow the ink sample to enter until it reaches the top of the thinnest part of the pipette. Squeeze and release the bulb until only the thin part of the tube contains ink.

NOTE: It is important to only fill the thinnest part of the pipette to prevent the ink from excessively spreading on the paper chromatography sheet. To finely adjust the volume of liquid in the pipette, try squeezing in the middle of the pipette, rather than on the bulb.

5. Gently TOUCH the tip of the pipette to the sample origin line on the left side of the chromatography sheet and slowly squeeze the pipette to ADD the CS sample to the paper chromatography sheet.

6. RINSE the pipette by sucking up distilled water and expelling it into the sink. REPEAT the rinse an additional two times to ensure the pipette is clean.

7. Using the rinsed pipette, REPEAT steps 4-6 for each of the remaining suspect samples, remembering to thor-oughly rinse the pipette after each sample has been added to the paper chromatography sheet.

continued

1. 2. 3.

5.

A B C

D E

8. 9. 10.5min.

11.

1 cm

7.6.

4.

Fill ONLYthinnest

part.

RINSE3 times.

DRY

MARK DRY

12. 13. 14.5

min.30min.


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Module II: Paper Chromatography of Ink Samples, continued

8. ALLOW the samples to dry on the paper for 5 minutes.9. While the samples are drying, ADD 20 mL of solvent to the beaker. The solvent should cover the beaker to ap-

proximately 0.5 cm deep. NOTE: Add or remove solvent until it is 0.5 cm deep. Too little or too much buffer can affect the final re-

sults. 10. Carefully PLACE the prepared paper chromatography sheet into the buffer. The side containing the dye samples

should be pointing down towards the solvent. NOTE: Only the bottom of the paper chromatography sheet should be submerged in the solvent, do not

allow the paper to fall into the beaker. If necessary, you can tape the chromatography sheet to the top of the beaker to keep it upright.

11. COVER the beaker with a sheet of plastic wrap.12. ALLOW the solvent to migrate up the paper chromatography sheet for 30 minutes, or until the dye front is 2

cm from the top of the sheet.13. REMOVE the paper chromatography sheet and lay it flat on a paper towel. Using a pencil, MARK the location of

the dye front.14. ALLOW the paper chromatography sheet to DRY on the paper towel for 5-10 minutes, or until the solvent has

completely evaporated.

continued

1. 2. 3.

5.

A B C

D E

8. 9. 10.5min.

11.

1 cm

7.6.

4.

Fill ONLYthinnest

part.

RINSE3 times.

DRY

MARK DRY

12. 13. 14.5

min.30min.


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Evaluating the Samples

15. MEASURE the distance that each spot has migrated in each ink sample. RECORD your results in Table 1. When identifying how far a compound traveled, measure from the center of the spot. Additionally, if a compound has more than one component, measure the distance migrated for each of them.

16. MEASURE the distance that the solvent front has migrated and record your result in Table 1. 17. Using these values, CALCULATE the Rf for each dye component in each sample.

Rf = (Distance sample migrated) (Distance solvent migrated)

18. COMPARE the composition of inks and Rf values for each of the suspect pens to the ink from the ransom note. DETERMINE which pen may have been used to write the note.

Module II: Paper Chromatography of Ink Samples, continued

Solvent Front

Ransom Note

Sample A

Sample B

Sample C

Sample D

N/A

Distance Travelled RfTABLE 1

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Study Questions

Answer the following study questions in your laboratory notebook or on a separate worksheet.

1. What is a questioned document?

2. Explain the difference between forensic document analysis and graphology.

3. Explain the principles of paper chromatography. How does the solvent separate the dye samples?



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Instructor's Guide

Preparation For: What to do: When: Time Required:

Module II: Paper Chromatography of Ink Samples

Prepare solvent. Anytime before performing the experiment. 10 min.

Anytime before performing the experiment. 5 min.Module I: Handwriting Analysis of the Ransom Note

Provide handwriting samples in Appendix A.

Up to 1 day before performing the lab. 15 min.Aliquot ink samples.

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INSTRUCTOR'S GUIDEEDVO-Kit 196 Write to a Fair Trial: Forensic Handwriting Analysis

NOTES TO THE INSTRUCTOR

This lab is designed for 10 lab groups. Class size, length of laboratory sessions, and availability of equipment are factors which must be considered in the planning and the implementation of this experiment with your students. These guidelines can be adapted to fit your specific set of circumstances.

If you do not find the answers to your questions in this section, a variety of resources are continuously being added to the EDVOTEK website. In addition, Technical Service is available from 9:00 am to 6:00 pm, Eastern time zone. Call for help from our knowledgeable technical staff at 1-800-EDVOTEK (1-800-338-6835).

Safety Data Sheets can be found on our website:www.edvotek.com/safety-data-sheets

Pre-Lab Preparations

In this experiment, students will perform two linked modules to identify the author of a ransom note. Module I involves analyzing handwriting samples from four suspects and the ransom note, while Module II uses paper chro-matography to separate simulated ink samples derived from the ransom note or from pens belonging to the four suspects. The modules can be performed in any order and on the same or separate days.

There are 5 total handwriting samples that can be located in Appendix A. Four of the samples are labeled as Sus-pect A-D, and the final sample represents the ransom note found at the crime scene. Handwriting samples should be provided, either printed or digitally, for students to use in Module I.

Preparation of Dye Samples

The sample dyes are provided pre-diluted and are ready for use by the students.

1. Label 10 snap-top microcentrifuge tubes for each suspect, A-D. Label an additional 10 microcentrifuge tubes as CS for the crime scene sample.

2. Pipette 10 µL, or one small drop, of each dye sample into the matching tube.

3. Distribute the suspect and crime scene samples to each group.

Preparation of Paper Chromatography Sheets

The paper chromatography sheet should be divided into 10 equal segments, approximately 8 cm x 10 cm in size. Each group will require one sheet for Module II.

Preparation of Solvent

1. Combine 225 mL of 100% isopropanol with 75 mL distilled water and mix well.

2. Dispense 30 mL of solvent for each group into small beakers. Cover the beakers with plastic wrap to prevent evaporation.

MODULE II is designed for 10 groups.Each Group should receive:• 30 mL solvent• 1 paper chromatography sheet• 5 ink samples• 1 small transfer pipet


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INSTRUCTOR'S GUIDE Write to a Fair Trial: Forensic Handwriting Analysis EDVO-Kit 196

Expected Results and Analysis

MODULE I: The results from the handwriting analysis will identify multiple similarities and differences between the samples and ransom note. The handwriting from Suspect C should most closely match the ransom note. Potential distin-guishing marks include punctuation and flourishes on letters, common misspellings, and the spacing or slant of letters.

MODULE II: Representative chromatography results are shown below. Each group will likely have slightly different results and Rf values, depending on the amount of sample spotted and length of time that the samples were allowed to migrate.

CS A B C D

Distance Lane travelled (cm) Rf

4.5 N/A

0.5 0.111

3.5 0.778

0 0.000

1.75 0.389

3.5 0.778

0 0.000

2.25 0.500

3.5 0.778

0.5 0.111

3.5 0.778

0.5 0.111

2.5 0.556

3.5 0.778

CS

A

B

C

D

Solvent Front

Crime Scene(Ransom Note)

Suspect A

Suspect B

Suspect C

Suspect D

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INSTRUCTOR'S GUIDEEDVO-Kit 196 Write to a Fair Trial: Forensic Handwriting Analysis

Please refer to the kit insert for the Answers to

Study Questions

Appendix ASuspect Handwriting Samples & Ransom Note

Suspect A

Suspect B

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APPENDICESEDVO-Kit 196 Write to a Fair Trial: Forensic Handwriting Analysis


Suspect C

Suspect D


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APPENDICES Write to a Fair Trial: Forensic Handwriting Analysis EDVO-Kit 196


Ransom Note

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APPENDICESEDVO-Kit 196 Write to a Fair Trial: Forensic Handwriting Analysis

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