Module 5 - Polygraph Testing & Forensic Document Analysis

Chromatographic Analysis of a Mock Ransom Note
(Optional Activity)

Purpose:

To identify the pen used to write a mock ransom note.

Materials:      

• tape
• scissors
• paper towels
• ruler or tape measure
• piece of blank white paper           
• 2-3 clear glass jars or clear drinking glasses
• 3 different black pens or 3 different blue pens   
• acetone (nail polish remover) Caution do not drink or let acetone get onto your eyes ! 
                         

Procedure:    

Part 1:  Creating 3 Comparative Ink Samples

1. Cut out 3 narrow but long strips of blank white paper.  Make sure each strip of paper will fit inside each jar/glass.
2. Near the top of each paper strip write down the following in pencil:   A, B, & C.        
3. Place 1 large dot 2 cm from the bottom of each strip of paper using a different pen for each dot.  Keep track of which pen you used to create each dot.

4. Place 2 capfuls of acetone into each of the 3 jars/glasses.
5. Now place each of the 3 paper strips into the 3 jars/glasses.  The bottom 1 cm portion of the strip should be submerged in the acetone, but do not allow the ink dot to get submerged - the acetone needs to be below the ink dot.  ( To prevent the paper strip from slipping down into the acetone you can tape it to your glass.)
6. Allow the strips to remain in the jars/glasses for about 5  minutes or until the acetone has past each ink dot. You will notice each of the ink dots separating in a distinct way due to the upward absorption of acetone into the paper. 

7. Remove each of the 3 strips after the acetone has just been absorbed  past each ink dot.  Place the strips on a paper towel. These 3 samples will serve as comparison samples to your mock ransom note.
8. Pour the acetone in each of the 3 jars/glasses down a toilet.  Keep 1 of the jars/glasses for part 2 of this experiment.  If you used drinking glasses - do not drink from any of these until each has been thoroughly washed with soap and water.

Part 2: Determining Which Pen Wrote the Mock Ransom Note

1. Have a friend or relative write a mock ransom note using 1 of the 3 pens you used in part 1 of this experiment (eg. “Hand over 1 million dollars or else!!”).  Try not to look at which of the 3 pens they use – it’s your job to figure out which one they used.  Be sure to tell your friend/relative to remember which pen they used!
2. Place 3 capfuls of acetone into a jar/glass.
3. Cut a strip from mock ransom note and place one end of this strip in the jar/glass containing acetone.  The bottom 1 cm portion of the strip should be submerged in the acetone.

4. Allow the strip to remain in the jar/glass for 5-10 minutes or until the acetone has past at least the first 2-3 letters in the mock ransom note.
5. Compare this mock ransom note with your original 3 ink strips you completed in part 1 and try to identify which pen was used to write it (see 2 photos below).

Can you determine which pen was used to make this ransom note? Click here for the answer.

Did you know?

In the early 1980’s, a German publishing firm claimed to have 27 volumes of the diaries of Adolf Hitler. Forensic handwriting experts were called in to determine the authenticity of these priceless historically significant documents.  All the experts agreed that the diaries were written by the same person - however this neither proved nor disproved that they were written by  Hitler.

The truth was revealed after analysis of the paper and ink used in the dairies.  Using ultraviolet light, forensic document experts discovered that the paper contained a bleaching agent introduced in 1954 - well after Hitler’s death in 1945.  Analysis of the ink revealed that it only been on the paper for about a year - again further proof the diaries were an elaborate forgery.

Continue onward to the Lesson 3 Assignment.