Just joining us today? Be sure to check out Day 1, Day 2, Day 3 and Day 4— where I cover everything from lifting fingerprints off of skin to blood. This is my last post about my time at SIRCHIE. I hope to have another experience like this very soon!
Originally posted July 13, 2012:
It is always sad when something ends. And despite wanting to get back home to my garden, I didn’t want my time at SIRCHIE to end. There is so much about evidence collection that I still need to learn! Clearly, my fictional detectives will be deficient until I can get myself enrolled in another forensics class. Alas, we can’t all be perfect.
That said, I cannot believe how much I was able to learn this week. The first four days were fantastic, a great deal of information was packed into Day 5. Footwear, serial number restoration, theft detection… and that’s just the beginning.
Why don’t we start with footwear? Did you know, for example, that footwear is often the most overlooked clue at crime scenes? And yet footwear can place a suspect at a scene. No, it isn’t as definitive as a finger print or DNA. But it is certainly a starting point.
Now, if you are a detective, you can dust for footprints the same way you’d dust for fingerprints. They may or may not come up. If you find a visible footprint, it can be lifted using the same type of tape that is used to lift fingerprints. In your search for blood, perhaps you will have a bloody footprint revealed by Luminol. Or maybe you’ll find a footprint outside in the mud, in which case you will need to take a plaster cast of the print.
Making a plaster cast of a footprint.
Let’s move on to serial numbers. Any gun that is manufactured in the United States is imprinted with a serial number. Criminals like to file these things down so that the gun cannot be identified. The thing is, serial numbers can be restored. A little sanding. A little acid. This technique will also work on restoring car serial numbers.
I was able to bring up the number!
Next up, theft detection. Theft detection powder is really, really hard to wash off. The harder you try, the more it stains. The lesson here is: don’t steal things!
Try getting THIS off your hands!
We also learned about presumptive drug testing. And seminal fluid testing. And brought up fingerprints on the sticky side of duct tape. All valuable tools when investigating crimes.
Presumptive drug test.
I think the main thing I came away with this week is that there is no such things as a perfect crime. Oh sure, they may exist in fiction, but in reality, there are just too many tools out there for catching the bad guy. All it takes is one piece of trace evidence, or a tiny bit of DNA, or a sliver of footprint, or a partial fingerprint…
