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Arson Science Rewritten
An anonymous reader handed us a link to an AP story about advances in the science of arson investigation. Many assumptions about fire, long held by investigators, have been overturned in recent years as scientists have come to understand concepts like 'flashover'. The repercussions of these findings is having an effect not unlike the use of DNA in crime-solving; people are being set free, and old cases are being re-examined. From the article: "Significantly, flashover can create very hot and very fast-moving fires. And it can occur within just a few minutes, dashing the concept that only arson fires fueled by accelerants can quickly rage out of control. The studies began to chip away at the old beliefs -- critics call them myths -- but it took years. Through the 1980s, texts at the National Fire Academy in Emmitsburg, Md., still taught the traditional techniques. It wasn't until 1992, when a guide to fire investigations by the National Fire Protection Association -- 'NFPA921: Guide for Fire and Explosion Investigations' -- clearly laid out, in a document relied upon by authorities nationwide, that the earlier beliefs were wrong."
you would be skeptical about the need for "accelerants". If you've ever seen a fire move through a room, it can go from a small area to engulfing the entire thing in less than a minute without any help from gasoline etc. I'm pretty sure that what happens is that the heat from the small fire vaporizes ordinary non-volatile things, like household furnishings or materials, and those vapors then act as the accelerant.
I know there was a case a few years ago where an "arsonist" in TX was executed for having killed his family, and within less than a year it was established that he was innocent.
I'll just say, the idea of someone being executed based on expert testimony from arson investigators, who are not even scientists, is appalling. Experts are only right until some new piece of knowledge comes along and changes the field.
And Jay Leno made jokes about me getting set on fire in prison. And all the inmates were so aglow with inner certainty as I was gang raped to death. Gosh, I guess no harm, no foul.
-signed, dead guy who was obviously guilty
I used to be a volunteer firefighter and also served as a fire investigator. My experience began around 1981 or so; later (late 90s), I worked for a Police Department doing crime scene work and part of that was fire investigation.
From TFA:
Up until the 1990s, this is what fire investigators were taught:
Fires always burn up, not down.
I was NEVER taught that; just the opposite. Fires tend to burn up FASTER than they burn down, but geez, anyone who has ever actually WATCHED a fire burn knows this statement is nonsense.
Fires that burn very fast are fueled by accelerants; "normal" fires burn slowly.
I was NEVER taught that; just the opposite. We were taught that accelerates were ONE WAY a fire MIGHT burn faster than you would expect under similar conditions. We were also taught that is EXTREMELY difficult to gauge how fast a fire "should have" burned. I did my first chemical test on fire debris in 1986 using GC/MS via a very simple headspace analysis on a sample that the state lab sent back as negative (my test was positive for something, perhaps ambient artifacts, but was an educational run, not an 'official' test). With the negative test result, we sure did not try to use evidence of 'how fast that fired burned' to assert the presence of an accelerant.
Arsons fueled by accelerants burn hotter than "normal" fires.
Somebody is oversimplifying the concept of "fire load" here. There are a WHOLE LOT of things than can make a fire burn hotter than 'normal.' In fact, as a common theme I am trying to represent, "normal" is not a well defined term for real-world fires. Rural firefighters and investigators certainly knew this before 1992.
In fact, this statement glosses over another issue about arson - they often, quite often, don't involve 'accelerants' at all.
The clues to arson are clear. Burn holes on the floor indicate multiple points of origin. Finely cracked glass (called "crazed glass") proves a hotter-than-normal fire. So does the collapse of the springs in bedding or furniture, and the appearance of large blisters on charred wood, known as "alligatoring."
The clues to arson are clear?? Man, I clearly remember in the early 1980's being taught exactly the OPPOSITE of what this article says was the "norm" back then. Perhaps it was taught somewhere, but not in RURAL North Carolina. Absolutely NONE of these "clues" are evidence of arson - only of certain fire conditions.
What we were taught in our arson investigation classes, and what I came to learn through experience, is that arson was/is and EXTREMELY difficult crime to prove. That means it is difficult to prove that a fire was arson, much less who did it.
Truthfully, based on my experience, I don't see the point of this article. It asserts 'beliefs' about fire investigation pre-1992 that just are not true.
And finally, the article gives the tragic story of the Lee family that occured in 1989. While presenting NONE of the evidence that was used to convict him, the story creates the straw man that just because it was 1989 and fire investigation changed (around then, according to the article), he must be framed. I don't know of his guilt or innocence, but that's a might big leap of logic.
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Why the heck should all houses in this country be made of wood? Haven't you guys heard of concrete? Or good old bricks? Seriously, this is crazy.
That has nothing to do with the article.
...if all your furnishings were also made of concrete, brick and cement.
Oh, blows your assertion out the window, you say?
Really, though, what did you expect from Texas?
Link
The only people in the case with a conscience are the jurors, the prosecutor and the judge had no qualms. That's not really a surprise though, not too many defense attorneys become judges. In fact, the more people you imprison as a prosecutor, the better your chance to become a judge or hold public office - this combined with prosecutorial immunity - and the fact that charges are rarely filed against prosecutors who engage in clearly illegal behavior such as destroying evidence - is why the legal system in the USA is so fucked up.
And, as you can clearly see, the idiots on the juries on each and every single one of these cases ate the bullshit the prosecution's expert witness threw at them. The lack of funding to defense attorneys by the state ensures that the prosecution's witness is the only one your average jury will see. And because most juries are composed of people who have barely completed what passes for a "high school education" in this country, the will smile and nod their head and convict you.
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Which moron modded this redundant?
that this thread will turn into a flame war.
My script don't crash! She crashes, you crashed her!
Tried reading the article but my Sony laptop caught on fire.
Bad form to reply to the moderators as an AC.
After something like 40 years of this being accepted, someone actually tested it. Result: no freaking correlation at all. The variation in composition of bullets within a given box was the same as variation among bullets from different boxes, purchased years apart. This is a completely worthless forensic technique.
Or consider early DNA testing. Up until at least the mid '90s (I don't know what they do now) a DNA test only looked for matches at a small number of base pairs. For any given DNA sample tested, there would be thousands of people in the world that matches that sample. What this meant was the the scientifically correct way to use DNA testing was to find your suspects using traditional police techniques, and THEN use a DNA test. If you had, say, 3 good suspects, and one of them had a DNA match, then that was very good evidence against that suspect. Unfortunately, sometimes it was used the other way. They'd start with the DNA, match it against whatever samples they had on file, and if they got a match, they'd go after that person. That's bogus.
If you look into the science behind much police investigation, you get this strange feeling you've fallen through some kind of wormhole and gone back to the early 19th century. It's amazing how much in common use has not been rigorously tested and peer reviewed by real scientists.
pack it around another explosive such as a quarter stick of dynamite and you should get a hell of a show
Snowden and Manning are heroes.
What is probably the single most annoying thing about fire investigation- from the investigator's perspective- is that arson is a terribly difficult crime to prove. Without a witness or some form of photographic or video evidence where an individual physically lights something on fire, the crime of arson is difficult to prove. As an instructor long ago put it to us: A man walks into a structure, and then walks back out. Later, it catches on fire. Houses burn all the time- bad wiring, gasoline stored near a gas water heater, cigarettes left burning. But causality- that that fire was intentionally set, and was set by that individual- may be difficult to prove.
In that regard, arson can be more difficult to prove than murder. With murder, there is frequently trace evidence with everything from blood droplets to weapons used, that can associate the murderer with the crime. With arson, in many cases there is heavy fire, smoke, and water damage, as well as the difficulty in proving that a fire started intentionally versus accidentally. Trace evidence such as gasoline found on the shoes of the accused arsonist can often be explained by more mundane events, such as spills at a filling station.
Making things worse, the folks who investigate are often poorly- or incorrectly- trained, and sometimes don't even want the job. Things are changing and candidates are frequently better educated than they have been in the past, but it's still a little rough around the edges. There aren't too many investigators in the field with advanced degrees, and a week or two of schooling (Arson I and II) at a state fire academy or the National Fire Academy are considered enough to get to work in many cases. 40 hours of fire investigation training, and you can help in putting people behind bars for what is considered a heinous crime such as arson of a habitable structure.
Sometimes investigation doesn't even start with the fire itself. Financial records are often scrutinized to determine if the accused would benefit financially. Business not doing well? Maybe it was torched. Home being remodeled? Maybe a convenient excuse to collect on insurance because of some major construction issues that existed. Upside down in your auto loan and gas hit $3 a gallon? That Yukon sure burns good!
Put all these together, and it's little wonder that some of the folks accused and convicted of this sort of thing are convicted and jailed. Many are poor, and get lousy lawyers- juries are likely to convict on scant evidence when the alternative is to let a possible firebug out on the streets.
Fortunately, there are improvements, and the standards for training have gone way the heck up in past years. Certification under some standard for training is often required for the job, as well as continuing education to stay on the job. Engineers, chemists, modelers, and physicists tackle some of the more difficult issues with lab tests to back up what's being said in court. It's one thing to say that a steam pipe at X degrees for Y years can eventually cause enough pyrolysis of nearby wood to create open flame; it's another to have some PhD back it up with experiments that prove it, possibly exonerating the accused.
Sometimes folks believe strange things from way the heck back in their training. This is part of the legend behind "spontaneous human combustion." The '921 says in it somewhere in a straightforward (and vaguely comforting) manner that humans do not spontaneously combust. Now only if we can do that with the other bits of legend that investigators have clung to over the ages.
Probably somebody with Mod Points, you insensitive clod
How many beans make five, anyhow ?
Here is some interesting information from a book on my shelf on Arson:
From: Fire Investigation; DAÉID, NIAMH NIC; CRC Press, Boca Raton, FL, USA, 2004. ISBN: 0-415-24891-4
(Excerpt: Chapter 1)
AIT: Automatic Ignition Temperature (as in 451 Fahrenheit)
In general, if arson investigation used to be like TFA states, then yes, I'd say that it has come a long way baby
I would be hard pressed to find a recent building (less than 200 years old) which is not in cut stone, concrete, brick, or parpaing (concrete already made in the form of a big brick with a empty room in the middle). Sure there are *some* wood house, for example in some region near the german/french frontier, old house which are built with wooden raster and some sort of filling, generally they are "kept" as historical heritage. Maybe also those garden pavillion. But the rest , the bulk, is definitively not in wood. I also suspect that in many part of the developping world, it is easier to deliver 2 tons of concrete to build a house than 2 tons of woods, at least the place where I visited, where the people were not living in slums out of metal sheets, they were living in concrete houses or high rise.
Actually is there many country which in the recent years build anything out of wood in mass except canada/US ?
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I'll just keep holding this match I've lit because fires don't burn down so my fingers will be safe! Ow, that hurts!
Nice factual reporting there.
Regrettably, this doesn't come as a surprise. In my own field we have the example of "voiceprint analysis", where "analysts" claimed to be able to identify a suspect's voice by comparing two spectrograms. This was complete and utter nonsense. There was no evidence that human beings have unique voices, no underlying theory of differences among voices (since almost all research focussed on abstracting away from individual differences so as to understand the acoustic basis for speech perception), no published description of the technique by which the comparison was made (which was proprietary) and no properly documented studies of the efficacy of the technique. Even worse, there were cases in Great Britain in which phoneticians testified solely on the basis of their ears that "the voice [on the tape or wherever] is the voice of the defendant and could be that of no other person in the world." If your lawyer didn't know enough to find a real expert to debunk this nonsense, you could be in a lot of trouble.
As was said earlier, it's damn near impossible to get an arrest for arson, much less a conviction. We had a guy admit to trying to torch his car for the insurance. He even wrote a confession and signed it, in front of my father and sheriff's deputies, and the DA let him off.
Arson investigation is grueling, filthy work. Hours on hours of rooting around in the rubble that was someone's home or business; sorting out the evidence from the disaster.
Fellow nerds, even though this shows that fire investigation is still an evolving science, go thank a firefighter or investigator for their service anyway. It'll make their day.
"Slapping lipstick on a pig does NOT make it Natalie Portman. Paris Hilton, maybe, but not Portman." - UncleTogie
And works with almost any fine powders too (flour,
whenever he sees a certain apache chief, he grows wings...
Dig the Byrds ref (Turn! turn! turn!)... I picked up a 28-track best-of for £2.99 on a lunchtime whim a few years back, and it blew me away - definitely underrated by ver kidz today, IMHO. That said, I have no Beatles, or Stones, or indeed much else at all from the 60s (apart from some Who) ... Prog didn't really get going until 1970 :)
Everything I needed to know about life, I learnt from Blake's Seven
Many of you across the pond won't be familiar with this disaster, but it's as good an example of fire spreading quickly without accelerants as you'll ever see. It all started when someone dropped a cigarette, and within a few minutes a hundred-metre long wooden stand was a goner, killing dozens of people. There's a video of it on YouTube, although I should warn you that there's one or two scenes in it which I personally find slightly difficult to watch.
I live in Tenerife, a Spanish territory off the West coast of Africa... Houses here are all block and concrete, with tiled floors. The floors are poured concrete too.
Back in the UK most houses are built out of brick with wooden floors, but more modern buildings tend to have an absence of wood. In the UK however floors tend to be carpeted. There's not a problem with brick walls as they're all made of two walls with insulating in the middle, so they're actually quite warm in the winter.
For me, a chap from England living in Spain I'm not sure I've ever been in an all wooden structure bigger than a garden shed in my entire life.
...I was just arson about!
I'm reminded of that old racist saying about Asian countries--they just don't value life the same way we do. Only rather than some unspecified Asian country, it's Texas, and unlike the racist generalization, this one happens to be true. They just don't value life the way civilized places do. If the executed is black, they don't care at all. If the executed is white, then they care a little bit, but nothing more vehement than "it's a damned shame." You could have 10 consecutive executions that turned out to be innocent and if the Supreme Court stopped capital punishment, they'd still hate the courts for interfering, and they'd think you threw out the baby with the bathwater. Even adjusting for my latent misanthropy, there is something rotten in the culture of that state.
Now obviously, being cleared 15 years after your first conviction doesn't count. Nor does having the chief witness recanting their testimony.
I don't know the first thing about the case, and, given that your source of "information" seems to be the American Communist Liberties Union, I wouldn't trust a single aspect of your recounting of the facts of the case, but, if we assume for the sake of argument that "the chief witness" recanted her [or his] testimony, then the fault here lies not with The People of the State of Florida [i.e. the prosecution], BUT RATHER WITH "THE CHIEF WITNESS" WHO PERJURED HER- [OR HIM-] SELF!!!
Human courts are only as good as the human witnesses who choose to honor [or dishonor] their oaths to speak the truth, the whole truth, and nothing but the truth.
If we are a nation of liars, who dishonor our sacred [well, really secular] oaths, then we will get the court systems we deserve.
I passed the parent on to a friend of mine who happens to be a DA with 20+ years experience in a major southern California jurisdiction. I got the following reply:
1. Prosecutors who do things like destroy evidence get fired and disbarred. Even in Texas. There are canons of ethics, business codes and bar rules for every jurisdiction, that impose on prosecutors the duty to "do justice", representing the interests of all the residents of the jurisdiction, including the accused. Do individual prosecutors occasionally cheat? Sure, but when they get caught (see below for appeals)they give their office a black eye, they lose their jobs, their livelihood, and the conviction for which they cheated. Prosecutorial misconduct of this level is an automatic walk for the defendant on appeal.
2. Prosecutors have a higher standard of ethics imposed upon them than defense attorneys. The prosecutor, again, is required to do justice. The defense attorney's standard is to help his client in virtually any way possible. Everyone in the legal profession knows this.
Bad prosecutions more often arise out of poor police investigation, or personal failings of the prosecutor involved, such as cowardice, apathy, or stupidity, rather than from dishonesty.
3. Lack of funding to defense attorneys? Let's break this down: public defenders get paid out of public funds, at exactly the same pay rate as prosecutors in the same jurisdiction, and while they have pretty heavy case loads, they usually have more time to put into a serious trial than private defense attorneys. Private defense attorneys either get paid by their clients or by the state if the client is indigent. If the accused can't afford experts to examine the evidence or testify about their area of expertise, those experts get paid by the jursidiction - that's you and me and every other taxpayer. There is virtually no limit to how much of the public funds that a defense attorney can expend on experts, so long as there is some plausible reason for having them in the defense. Failure to provide funds for an arguably relevant expert witness for the defense is a denial of due process, and again results in reversal on appeal.
The prosecution does have access to police labs and the criminalists who work there, who testify in areas of their expertise. However, there are plenty of private criminalistics experts that the defense can call. If the police criminalist finds evidence that weakens the case against the accused, the prosecutor is required to turn it over to the defense. If the defense criminalist finds evidence that strengthens the case against the accused, there is no duty to turn that information over to the prosecution. And if the first defense criminalist doesn't help the defendant enough, the defendant can keep shopping on his own dime, or on the public's, if he can convince the judge of the merit of his request. Prosecutors' offices have to work within their budgets - which is why the prosecution generally calls fewer expert witnesses in the big trials.
4. On the subject of appeal, there are also publicly paid defense attorneys for a convict who wishes to appeal his conviction. It's one of the reasons why there are so many frivolous appeals jamming appellate court calendars. The convict has the right to demand that the appellate court review his trial to find some error, even if his appellate lawyer can't find anything specific to complain about. All on the taxpayer's account. So why not appeal? It costs the appellant nothing, and it's something diverting to do while serving his time.
5. Judges become judges in 1 of 3 different ways: They are elected in a general election for a vacant seat, they are directly appointed to a vacant seat by the governor, or they become temporary judges called "court commissioners", who can be but are not always appointed judges by the governor thereafter. The only difference between a court commissioner and a regular judge is that the partie
Remarkably similar in content and style to http://www.newscientisttech.com/channel/tech/mg192 25761.100-arson-evidence--shot-down-in-flames.html published November 6th, 2006...
Omeganon
well said. Nicely argued, concise.
Well, technically, once a person is executed it becomes impossible to "prove" his innocence because no further trial will ever be conducted. It's rather pointless to put a corpse in the defendants chair...
there has never been a case of significant evidence coming to light of an inmates innocence after he had already been executed
There has never been a case of innocence of an executed prisoner, because the process for determining that evidence is abandoned--perhaps it's because it's pointless, and perhaps it's because those that profit (politically) from execution of prisoners have no reason desire to see themselves proven wrong.
Of course there's a reason to put a corpse in the defendant's chair: to verify our methods of investigation so that other innocent victims can be spared.
--
$tar -xvf
You haven't heard of Weyerhauser? They own lots of tree farms in the US, and I'm sure that there are equivalent companies with similar tree farms in Europe. Russia has lots of land suitable for timber farming, should the need arise.
Okay, I think I understand this now. Scientists, beginning in the '70's, studied and quantified what we firefighters already knew and was already in our IFSTA (International Fire Service Training Association) Fire Science manuals and then twenty years later the NFPA got around to writing a revolutionary guide for fire investigators thus changing the way arsonists are prosecuted, freeing those who were unjustly accused and scolding firefighters for their ignorance. Yeah, clear a soot.
My god. To think I wasted 24 years caring about nothing more than protecting life and property.
That would be Kenny Richey.
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Dog is my co-pilot.
I don't think this is the most tactful ending to an article about a girl who got burned to death!
I like my coffee the way I like my women - roasted and ground up into little tiny pieces.
- Presence of accelerants - look for pour patterns on the floor.
- Multiple points of origin - clear indicators that the fire started in two, three or more places.
- Personal valuables missing - absence of photo albums, personal phone book by phone, pictures missing from wall, stereo, cameras, etc. missing. I once investigated a fire where I found ammo for five types of guns, but no guns, guitar strings and no guitars, clear evidence that pictures had been taken off the wall before the fire started and a gasoline pour pattern in the living room carpet that led to the front door.
- The insured - that's your most important clue. Look at his finances.
As I said, these are indicators. No one is enough, but taken together they can tell you what might be arson.Some mornings it's hardly worth chewing through the restraints to get out of bed.
When I wrote about them just not valuing life like the rest of us, I am addressing a specific, known, acknowledged trait. I'm not making a metaphysical generalization, but saying, again, that insouciance about the execution of innocent people means that you don't value human life very much. If Texans as a group were upset about it, it would change, but since it won't change anytime soon, and Texans don't seem very upset about it anyway as a group, it would be hard to draw another conclusion. What you're doing is ignoring the very specific criticisms I made and pretending that I'm just generalizing from nothing. If the people I'm calling cannibals are in fact cannibals, then the assessment isn't bigoted. Ergo, if the people I'm accusing of not valuing human life very much in fact don't value human life very much, then no, it's not a bigoted generalization.
I trained in 1979ish and then they were teaching how to fight flashover. One exercise involved a fully-involved brick "bedroom". Flames were up to the ceiling and spread across the entire room. The test: Put out the fire with a 1-2 second wide spray from a 2 1/2 inch hose. That's about 10-20 gallons of water.
The trick is don't spray the hay, spray the ceiling over the hay - that's where the heat is. This is opposed to the conventional technique of spraying "the base" of the fire.
The near-explosive boiling of water to steam takes away a coupla hundred degrees of temprature, and the sudden increase in humidity reduces the flame potential of aerable fuels like cloth, blankets, hay, etc ("aerable" as opposed to dense fuels like solid wood). The snuff-out is impressive.
I don't think the article is right about this being "new", although it's possible the info spread slowly in different regions.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
Where we once didn't have materials that could flash over in common use in the household...
Uh, talcum powder, wheat flour, any loose weave cloth used as wall hangings or bed linens, *sheet rock* (yup, get it hot enough, and it'll go up quite fwooshedly), Xmas trees, saw dust, in fact, anything that'll burn, if reduced to dust in the air, will flash over.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
Duh. Normally, hay is not found in a bedroom in any sizeable quantities. Brick walls were used so the fire school didn't have to build a new house for every exercise. Hay was used to simulate the semi-dense fuels commonly found in houses, such as furniture, beds, etc. Hay is a more realistic simulation than gasoline, liquid oxygen, basalt, etc.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.