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The_Ink_Goddess
04-12-2012, 12:28 AM
Okay, so I'm pretty sure CSI and the like have given me an inflated idea of what part DNA plays. In my WIP, a con artist switches identities with a similarly-built young woman who dies in a train crash and gets so badly burned that she can't be easily identified. Is it plausible that The Powers That Be wouldn't do a DNA test if they found obvious ID on her, such as a driver's licence?

Drachen Jager
04-12-2012, 01:31 AM
As long as they don't have a reason to perform a test they don't perform it. Everything costs money.

So, unless someone suspects the dead woman is other than the obvious, they wouldn't investigate at all, beyond the obvious investigation into the crash.

Even if they tested, where would they find DNA to test against? Is your con-artist's DNA on record?

amlptj
04-12-2012, 01:45 AM
This question depends on many factors. But I'm more inclined to say they would at least preform a simple blood test. Any body that goes through a morgue and is autopsied, a sample of blood is taken for analysis, to find out things such as blood type, alcohol level, and other such simple factors. This blood test could take a long time though if it is done in a big city where labs are usually overloaded with work.

In the case of a mass train crash where i'm assuming more then this woman died, it is possible a autopsy would not be preformed for the obvious cause of death, (which would be the crash) so you could get away without blood being taken if she had ID on her. Even without ID, the womans DNA would have to be on record to see be identified, usually dental records would be used before that of DNA in a case like this with trying to find out the identity.

Now if this woman died and then the con-artist takes her ID, then i feel you would be fine, the only way the con-artist would be truly caught is if the blood types didn't match, that would be an immediate red flag, but i dont see how she would get caught otherwise unless someone found out the real person was dead and was determined enough and able to get the real person's medical records to compare DNA somehow.

jclarkdawe
04-12-2012, 07:02 AM
Starting question is how many people are killed and how badly are the bodies mangled.

I doubt in a train collision in which bodies are burned beyond recognition would result in her having an ID on her body. Assuming it was actually on her body, it would have melted and burned with her body. And if she was carrying it in a purse or handbag, the force of the collision is going to send it flying.

Is this commuter rail or long distance travel? Identification procedures are markedly different between the two. With long distance travel, at least in the US, you have some idea who is on the train from the manifest.

Starting point is to examine the bodies for any identifying marks. Skin color, height, weight, scars, eye color, hair color, how hair in various parts of the body is cut, fingernail length, toenail color, personal effects (rings, necklaces) are all used to provide a preliminary identification. Depending upon how deeply burned the flesh is, tattoos can survive. Former broken bones will show up on x-rays. And then you have the famous dental records. Blood type, depending upon type, can also be used. (Some types are rare enough to work.) If at this point the medical examiner is confident about the identification, he or she calls it.

If identification isn't successful at that point, then DNA is used. Parents, children, or siblings are used for comparison DNA.

It's becoming harder and harder to have a misidentified body these days. Cost of DNA is a lot cheaper then screwing it up. You might want to look at Mass Fatality Incidents: A Guide for Human Forensic Identification (http://www.nij.gov/pubs-sum/199758.htm).

So might reaction is that it is possible, but becoming less and less probable. Rather then it being omitted, I'd find a way for it to be screwed up.

Best of luck,

Jim Clark-Dawe

blacbird
04-12-2012, 09:59 AM
Before DNA testing is done, it is likely that dental identification comparisons will be. Easier and cheaper, and often all that's needed. It would be damn hard to switch an identity in such a way that it would fool a dental comparison. And, as has been mentioned, what kind of identity document would survive a catastrophic conflagration that would so destroy a body that medical analysis (dental or DNA, or even simple blood typing) would be impossible?

Faking out a really serious post-mortem forensic identification is close to impossible.

caw

frimble3
04-12-2012, 11:45 PM
What if the victim wasn't badly burned? What if it was a big train wreck, lots of victims, and the con artist appears very similar to the victim - same build and height, similar hair and colouring, no distinguishing marks?
If there was some facial damage to justify any minor inconsistencies, but the (undamaged) ID found on the (slightly) damaged body was a match, would a medical examiner with a huge caseload figure it was an easy call and let it go?

jclarkdawe
04-13-2012, 04:53 AM
What if the victim wasn't badly burned? What if it was a big train wreck, lots of victims, and the con artist appears very similar to the victim - same build and height, similar hair and colouring, no distinguishing marks?
If there was some facial damage to justify any minor inconsistencies, but the (undamaged) ID found on the (slightly) damaged body was a match, would a medical examiner with a huge caseload figure it was an easy call and let it go?

In big mass casualty situations, they call in extra medical examiners. So caseload isn't an issue. Accuracy is.

And people have gotten good as this. If you don't use DNA, you have several various aspects that make for a positive ID.

Also, my guess is that any train wreck that's bad enough for a major fire is going to create body parts. You try to identify all the body parts as to who goes with what. It wouldn't surprise me that now in a major accident, each body or fragment thereof, has a DNA sample.

They're still ID body parts from 9/11 and taking advantage of some advances to get even more pieces identified.

Best of luck,

Jim Clark-Dawe

jclarkdawe
04-13-2012, 02:58 PM
How smart is your protagonist and how much thinking ahead does she do? If she's smart and planning ahead, I've got a plan for her.

If she's not, you're going to just have to rely on the ME screwing up.

Best of luck,

Jim Clark-Dawe

The_Ink_Goddess
04-13-2012, 11:54 PM
How smart is your protagonist and how much thinking ahead does she do? If she's smart and planning ahead, I've got a plan for her.

If she's not, you're going to just have to rely on the ME screwing up.

Best of luck,

Jim Clark-Dawe

She's pretty smart, but definitely smart (instinctive, quick-thinking) ather than book-intelligent, but she does a lot of planning ~ she is a con artist, after all. Please share the plan (if you haven't already and I just missed it already).

jclarkdawe
04-14-2012, 04:42 AM
Okay, we start with the fact that a good train wreck gets into the papers. With a bit of digging, your character can find the preliminary casualty list. She goes through the list, trying to figure out who she could be.

Once she finds a satisfactory possible victim, she does some background on the victim. Meanwhile, her buddy shows up at the police, saying he thinks his girlfriend, the protagonist, was on the train and he hasn't heard from her since the accident. And oh, by the way, she's the type that's likely to have sneaked onto the train, so of course she wouldn't be on the manifest.

He gives the authorities some DNA sample (hair brush?). The DNA is actually the victim's. But it goes in with the protagonist's name. DNA confirms the dead person matches the DNA. Meanwhile, the protagonist is showing up saying she shouldn't be on the list, cause here she is.

Net result is that the protagonist is positively identified as the dead victim, and the dead victim is declared alive. And all proved by the miracle of modern science.

Best of luck,

Jim Clark-Dawe

frimble3
04-14-2012, 08:48 AM
Okay, we start with the fact that a good train wreck gets into the papers. With a bit of digging, your character can find the preliminary casualty list. She goes through the list, trying to figure out who she could be.

Once she finds a satisfactory possible victim, she does some background on the victim. Meanwhile, her buddy shows up at the police, saying he thinks his girlfriend, the protagonist, was on the train and he hasn't heard from her since the accident. And oh, by the way, she's the type that's likely to have sneaked onto the train, so of course she wouldn't be on the manifest.

He gives the authorities some DNA sample (hair brush?). The DNA is actually the victim's. But it goes in with the protagonist's name. DNA confirms the dead person matches the DNA. Meanwhile, the protagonist is showing up saying she shouldn't be on the list, cause here she is.

Net result is that the protagonist is positively identified as the dead victim, and the dead victim is declared alive. And all proved by the miracle of modern science.

Best of luck,

Jim Clark-Dawe
That's ... brilliant. You've obviously given this a lot of thought. Covered both identities, with a minimum of fuss. Provided the MC's friend can get a DNA sample of the 'victim'. Which is probably what would make a potential victim 'satisfactory'.

Prophetsnake
04-16-2012, 07:54 AM
if there are relatives of the victim in your story, a relationship to them can be definitively shown if the police suspect something is wrong. DNA tests are not that expensive anymore (few hundred bucks) and they will spend it if they think a crime is involved. So, if your body shows up, and some indicates that the dead body's identity has been stolen, they're going to check through whatever means are at their disposal.

areteus
04-16-2012, 01:49 PM
This question depends on many factors. But I'm more inclined to say they would at least preform a simple blood test. Any body that goes through a morgue and is autopsied, a sample of blood is taken for analysis, to find out things such as blood type, alcohol level, and other such simple factors. This blood test could take a long time though if it is done in a big city where labs are usually overloaded with work.

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Those particular tests don't take long... however, DNA is a different matter because (especially from a blood sample) there is relatively little DNA to be tested (remember, only white blood cells have DNA, red blood cells don't). First you need to PCR it to amplify the sample to make sure you have enough to do all your testing (usually at least 3 - 4 hours, often done overnight) then you need to do the various tests you need to do such as genetic fingerprinting (which compares your sample to a known one - if you don't have a known sample there is little point in doing it) and that can take another few hours. In a busy lab with many tests to do, unless something is labelled as urgent it can take weeks to get a result back. It is not a case of getting in more medical examiners but getting more lab assistants and a lot of forensic science work these days is outsourced to companies and so it costs money...

I agree that they would look at dentals and other means of ID before they considered DNA. Plus they would get the DNA from a hair follicle or skin sample or mucus membrane sample rather than blood (more DNA avaiable to test).