Forensics Questions

Re: What's the liquid used on the cotton swab?

Moved this to the questions thread. and to Answer...
A presumed blood sample is first collected with a swab. A drop of
phenolphthalin reagent is added to the sample, and after a few seconds,
a drop of hydrogen peroxide
is applied to the swab. If the swab turns pink rapidly, it is said to
test presumptive positive for blood. Waiting for periods over 30
seconds will result in most swabs turning pink naturally as they
oxidize on their own in the air.
Optionally, the swab can first be treated with a drop of ethanol in
order to lyse the cells present and gain increased sensitivity and
specificity. This test is nondestructive to the sample, which can be
kept and used in further tests at the lab; however, few labs would use
the swab used for the Kastle-Meyer test in any further testing, opting
instead to use a fresh swab of the original stain.
Click to expand...

From Kastle-Meyer test
 
I know that they use forensic experts, but I do know there can be a bit of artistic license taken. That's fine, it's entertainment. But, I remember a CSI NY episode where they did a facial reconstruction, and they used a real forensic artist But the reconstruction was like a portrait of the victim, and that just can't happen in real life. We still don't know enough about the skull-to-soft tissue relationship to make them exact.
 
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Re: What's the liquid used on the cotton swab?

I was posting the same thing as Dizzney... editing it now...

See that's one of the few things they do bad at CSI, since it's only an ORIENTATIVE test (they use it as confirmation)
 
Okay, call me dumb, but is it blood spatter or blood splatter?

And if it is one of the two, what's the difference?

Forgive my stupid-ness. :confused:
 
CSI17 said:
Okay, call me dumb, but is it blood spatter or blood splatter?

And if it is one of the two, what's the difference?

Forgive my stupid-ness. :confused:
Click to expand...
Splatter is what the lay person calls blood spatter. Blood spatter is the term used to describe what happens to blood on impact, or injury, etc.
 
Sort of not a forensic question, but related to the lab. Is there actually such a thing as a PEAP counsellor? I tried to find it online but they only seem to mention it on CSI. Is there a real name for it? What do they do and why are they mentioned on the show?
 
Can someone tell me when (year) DNA testing was first used? I think it was mentioned on CSIs when they were dealing with cold cases and since DNA testing is now available they reopened some. I just can't remember the year.
 
The very first case solved using DNA was in 1986/87, in England. The first case in the USA was also in 1987.

On CSI, in Sweet Jane, one of the former detectives says "In '89? We were just reading about DNA. The only lab in the country that was doing that stuff was the FBI."

The first state lab in the US to do DNA testing was in Virginia, in 1989. Private labs were doing DNA testing in 1988.
 
Raynn said:
The very first case solved using DNA was in 1986/87, in England. The first case in the USA was also in 1987.

On CSI, in Sweet Jane, one of the former detectives says "In '89? We were just reading about DNA. The only lab in the country that was doing that stuff was the FBI."

The first state lab in the US to do DNA testing was in Virginia, in 1989. Private labs were doing DNA testing in 1988.
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Ah, Sweet Jane, I remember that episode. It was great and the dentist was creepy! Thanks a lot Raynn! :)
 
In the CSI: Miami episode "Internal Affairs", a man was killed from a blank at close range. Can the paper inside the shell casing really kill a person? I'm skeptical. Sure, the paper may have been going quickly from the gunpowder, but would it have enough inertia to travel through a guy's throat? Any input on this would be much appreciated :)

http://www.herbalmax.com/high-cholesterol-herbal-formula
 
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I'm finding this thread fascinating!

I have a question too. In the case of a analysing a footprint ( not fingerprint ) what technique would be used? I have heard and seen various tecnhiques including filling up the the footprint with plaster.

Happy crime solving!

JB
 
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