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Alsikepike
08-21-2017, 08:57 AM
I'm writing a story that involves an assassin killing a guy from a long distance with a conventional hunting rifle and attempting to frame someone else for it by planting a spent bullet casing with the framee's fingerprints on it. The authorities are unable to locate the bullet due to the location of the victim when he was shot, so they're stuck examining the casing. The phony bullet casing is almost two days old. Could modern forensics be able to tell the difference between a bullet casing fired today and one fired yesterday? And if so, how would they do it? What might prompt them to investigate what time a bullet was fired from the casing in the first place? I can't seem to find any sources online that can give a definite answer on any of these questions, so help on this would be very much apppreciated.

WeaselFire
08-21-2017, 09:21 AM
I have never seen a case where age of the casing came into issue unless the case was being argued by attorneys. Then a simple "Could this spent casing have been dropped at that spot earlier than the shooting? Or by someone else?" would likely be the way it gets handled. No prosecutor is going to trial with only a spent casing as evidence.

Jeff

cornflake
08-21-2017, 09:23 AM
I'm writing a story that involves an assassin killing a guy from a long distance with a conventional hunting rifle and attempting to frame someone else for it by planting a spent bullet casing with the framee's fingerprints on it. The authorities are unable to locate the bullet due to the location of the victim when he was shot, so they're stuck examining the casing. The phony bullet casing is almost two days old. Could modern forensics be able to tell the difference between a bullet casing fired today and one fired yesterday? And if so, how would they do it? What might prompt them to investigate what time a bullet was fired from the casing in the first place? I can't seem to find any sources online that can give a definite answer on any of these questions, so help on this would be very much apppreciated.

There's a reason you can't find it -- that's not a thing. Unless there's been some amazing developments I've not heard of very recently, there's no dating casings like that.

ironmikezero
08-21-2017, 10:10 PM
Be careful--you may paint yourself into a corner. The tech for determining the precise time the live round was fired based solely on examination of the spent case does not yet exist; or as cornflake so concisely put it, "that's not a thing" (-- not yet, anyway). If there are neither witnesses nor any other evidence, you have a problem. For example; if the investigators don't have the bullet, or the rifle, there is no direct evidence linking to the "found" spent casing to the crime; its circumstantial at best. The latent fingerprint means your "framee" will be interviewed. However, absent any further evidence, the investigation will stall.

cornflake
08-21-2017, 10:18 PM
To be clear, just in case the OP is unsure based on our comments -- there's no determining that from a casing at all. It's not like there are reports that say 'this casing was fired between one month and six weeks ago.' It's not about the specific or narrow timeframe, but that that's just really not a thing. We don't do that, date casings, in a general sense.

Now, if a casing is found someplace with, whatever, moss growing on it, or in a place that has elements, or that has deposited elements on the casing that can contribute to dating, that is a thing. A casing covered with three months growth of moss is a finding, though it's not much use, as it's hard to prove the casing landed there from ejection and wasn't moved, kicked, from some entirely other place that someone had been carrying around and dropped three months ago, etc. If it's an untouched scene then maybe but that's a really specific case and not what's in your scenario.

ironmikezero
08-21-2017, 10:47 PM
[/QUOTE]Now, if a casing is found someplace with, whatever, moss growing on it, or in a place that has elements, or that has deposited elements on the casing that can contribute to dating, that is a thing. A casing covered with three months growth of moss is a finding, though it's not much use, as it's hard to prove the casing landed there from ejection and wasn't moved, kicked, from some entirely other place that someone had been carrying around and dropped three months ago, etc. If it's an untouched scene then maybe but that's a really specific case and not what's in your scenario.[/QUOTE]

- Good point! Never overlook the totality of the surrounding context (time and place the spent case was found, environmental conditions, etc.); that may provide additional evidence. To keep your story from stalling, you're gonna have to give the investigators something else to work with--drop a clue here and there. Keep it plausible, pragmatic, and justifiable (within the rules of evidence admissibility in court--unless you're slipping into fantasy; then, it doesn't matter). Find a way to ratchet up the readers' interest and keep them engaged.

Shoeless
08-21-2017, 10:56 PM
It's mind boggling to me how educational some threads in AW can be. None of this information is currently useful to me for the writing I'm currently doing, but all of it is extremely enlightening.

talktidy
08-22-2017, 01:52 AM
It's mind boggling to me how educational some threads in AW can be. None of this information is currently useful to me for the writing I'm currently doing, but all of it is extremely enlightening.

Yeah, it like enrolling in the Open University http://www.open.ac.uk/
(http://www.open.ac.uk/courses/choose/ppcbrand?utm_source=google&utm_campaign=bauwales-brandexact&utm_medium=cpc&utm_content=mainlink&utm_term=openuniversity&gclid=Cj0KCQjwierMBRCHARIsAHl9i4Fw8pQjvAru6ZmW9Fzp 92F2yVKfd5_ZnZoHdYzTdzlqVKNiw3Ql6AAaAjHoEALw_wcB)

Thomas Vail
08-22-2017, 02:17 AM
I can't seem to find any sources online that can give a definite answer on any of these questions, so help on this would be very much apppreciated.

That's a clue that you're asking a question for which there is no real answer for. If you kept them all in a box, there'd be no way to tell which casing came from a gun fired two days ago, two weeks ago, or two months ago. The kind of chemical reactions which would age brass are the kind that take a long time to manifest, and generally mean it was exposed to the elements as well.

cmhbob
08-22-2017, 02:58 AM
The authorities are unable to locate the bullet due to the location of the victim when he was shot...

This pulled me up short. What do you mean here?

frimble3
08-22-2017, 05:56 AM
This pulled me up short. What do you mean here?
Purely speculating, but maybe the victim was on a boat when shot through, and the bullet ended up in deep water?

M.C.Statz
08-22-2017, 06:17 AM
Also, not that it exactly matches the phrasing of the original post, can't a bullet fragment and thus be useless from a forensic standpoint?

cornflake
08-22-2017, 06:44 AM
Also, not that it exactly matches the phrasing of the original post, can't a bullet fragment and thus be useless from a forensic standpoint?

They can and do fragment, but that doesn't necessarily render them useless. Rifling can be matched from sections, depending on what you've got (on both sides); you don't often get utterly intact bullets in their original shape once they've been fired and have impacted with pretty much anything.

Al X.
08-23-2017, 04:24 AM
I'm writing a story that involves an assassin killing a guy from a long distance with a conventional hunting rifle and attempting to frame someone else for it by planting a spent bullet casing with the framee's fingerprints on it. The authorities are unable to locate the bullet due to the location of the victim when he was shot, so they're stuck examining the casing. The phony bullet casing is almost two days old. Could modern forensics be able to tell the difference between a bullet casing fired today and one fired yesterday? And if so, how would they do it? What might prompt them to investigate what time a bullet was fired from the casing in the first place? I can't seem to find any sources online that can give a definite answer on any of these questions, so help on this would be very much apppreciated.

Associating a bullet with a casing is something that I do not believe is within current ballistics forensics. However, it is possible to identify a specific casing with the weapon it was fired from, by the striations on the case from the chamber and the firing pin indents, plus association of the bullet with a specific barrel is possible as well.