I spent the five happiest years of my life in a morgue. As a forensic scientist in the Cleveland coroner’s office I analyzed gunshot residue on hands and clothing, hairs, fibers, paint, glass, DNA, blood and many other forms of trace evidence, as well as crime scenes. Now I'm a certified latent print examiner and CSI for a police department in Florida. I also write a series of forensic suspense novels, turning the day job into fiction. My books have been translated into six languages.
On the shooter's hands, not very long. When we did GSR testing we would not do it if more than 4 hours had elapsed since the shooting. On clothing, it could depend on the type of material and how far away the item was--if it's a smooth fabric it would probably brush right off, but a more fuzzy type of thick material might get some particles stuck in it.
That was talking about primer residue. Gunpowder residue is bigger, heavier, and hot so it can fuse to some fibers or get 'stuck' to the item by the victim's blood.
I have never heard of that.
Okay, I am emailing you.
Because human bodies are in constant flux. Cells slough off, fluids wash out other fluids, but a stain on a piece of cloth doesn't change.
Forensic Scientist
Employment Lawyer
Starbucks Barista
No. Almost all blood enhancement reagents will not destroy the blood for DNA testing. I don't think it would affect confirmatory tests either, but If we wanted to do a confirmatory test for blood such as phenolphthalein we would probably just do it on a spot where the marks were smeared or otherwise not useful as fingerprints.
The coroner's or medical examiners office, or find a college with an anthropology major and ask one of the professors.
I actually don't know how a DNA analyst tells human from animal DNA, but I don't think it's very difficult. We have an easy field test called Hexagon OBTI that can tell animal from human blood in a matter of minutes.
-OR-
(max 20 characters - letters, numbers, and underscores only. Note that your username is private, and you have the option to choose an alias when asking questions or hosting a Q&A.)
(A valid e-mail address is required. Your e-mail will not be shared with anyone.)
(min 5 characters)
By checking this box, you acknowledge that you have read and agree to Jobstr.com’s Terms and Privacy Policy.
-OR-
(Don't worry: you'll be able to choose an alias when asking questions or hosting a Q&A.)