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Toilet Paper to the Rescue

24 Feb

TP

“I have a gun. Give me $300.”

Here’s a bit of advice: If you plan to rob a bank or a business, say a pizza joint, don’t write your “stick up” note on toilet paper and then leave the roll behind for the police to find when they search your home. If you do, you give the investigators much to work with in connecting you to the crime. Don’t believe me? Ask Eric Frey.

In this case, Frey left behind “indented writing” on the roll and, much to his dismay, investigators were able to match this “writing” that that on the note.

This is definitely an odd case of Forensic Document Examination.

Two other forensic techniques that could enter the picture here would be chemical ink analysis and fracture pattern assessment. The ink on the note could be chemically matched to the marker pen found at Frey’s residence and this could serve to further link him to the note.

Also, since no two things fracture, crack, or tear the same way, analysis of the torn edges could match the note paper to the roll—-if no other tissues had been torn away after the note was removed. The tear line between the roll and the note paper would match and this match is about as good as DNA or fingerprints. Such tears, like broken glass or chipped paint or broken sticks, are called fracture patterns and they are highly individual.

There is an entire chapter on the fascinating field of Document examination in my forensic books Howdunnit: Forensics and Forensics For Dummies.

Howdunit 400X533

FFD 400X600 copy

And a few links for you to explore:

A Simplified Guide to Forensic Document Examination: http://www.forensicsciencesimplified.org/docs/how.html

FBI Forensic Ink Analysis: http://www.fbi.gov/about-us/lab/forensic-science-communications/fsc/july2005/research/2005_07_research02.htm/

Glass Fracture Patterns: https://www.ncjrs.gov/pdffiles1/nij/grants/241445.pdf

Howdunnit:Forensics and my other Forensic Books: http://www.dplylemd.com/DPLyleMD/Books-Forensics.html

 
9 Comments

Posted by on February 24, 2015 in Crime Scene, Document Examination

 

9 responses to “Toilet Paper to the Rescue

  1. Laurie Stevens

    February 24, 2015 at 12:52 pm

    Always love your great forensic articles, Doug. I always share them.

    Like

     
    • D.P. Lyle, MD

      February 24, 2015 at 1:21 pm

      Good. Hope they spark some story ideas for all the writers out there.

      Like

       
  2. Sheila Lowe

    February 24, 2015 at 6:56 pm

    If it couldn’t be eyeballed, they would have used ESDA — electrostatic detection apparatus.

    Like

     
  3. dianahockley

    February 24, 2015 at 8:01 pm

    Now that was very interesting! Expect the toilet roll was the first item the team headed for when they got to the perp’s house! 🙂

    Like

     
  4. Irene McKenna

    February 25, 2015 at 9:24 am

    Another wonderful article! Thanks.

    Like

     
  5. Pat Marinelli

    February 25, 2015 at 11:03 am

    It always amazes me when a crime can be proved with things like towel paper, trash bags, etc. Great post. Thanks.

    Like

     
    • D.P. Lyle, MD

      February 25, 2015 at 11:18 am

      So true. I thought this one was particularly cool.

      Like

       

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