Are Victim Detection and Forensic Evidence Search Dogs reliable?

[Alfred R Jones]

Your argument is  based on a false analogy   ...  'a dog in another case was wrong,  therefore it is necessary to assume the dog in this  may have been wrong'

We do not  have  to look at the set of circumstances most likely to  'fit'  in with the cadaver dog's alerts

The dog's alerts are a  factual piece of evidence and what those alerts indicated will not be proven  (  or disproven )  by the imaginery scenarios you are presenting and asking others to comment on

Is this thread about EVRD dogs in general or about Eddie and Keela?

Are we not allowed to consider examples of other EVRD dogs in order to understand what issues may have affected the performance of these two dogs in particular?

Where have I stated that it is "necessary to assume" anything at all?

You don't have to do anything you don't want to, I thought however that if we took the EVRD dogs in this case to have been 100% reliable indicator that Madeleine died in the apartment then it would be interesting to discuss what that means in practical terms.  Perhaps you will be more interested in discussing this on a separate thread so I shall start one. 

I am not seeking to prove or disprove anything, I'm just having an informal chat on an internet forum.

[Cornelius]

It seems however that certain things have been ruled out as utterly impossible by certain people eg: Eddie could not have been susceptible to unconscious handler bias (why not?) and to reference another thread, that it is impossible to walk up a street in flip-flops without making a large amount of noise that draws attention to yourself (why not?)

In fact  probability theory and the laws of physics need to be suspended completely in order to come up with a detailed theory of Madeleine's disappearance which has the parents as the culprits and which takes into account all the known facts of this case.  If I'm wrong about that then I would be most interested to hear why.

Bearing in mind not even the investigative bodies know what actually happened (or not that they are telling the public) it is impossible to say at this juncture whether you are right or wrong. I would not know where to lay my purse. There maybe an answer forthcoming in due course or the whole thing may remain unresolved.

[Cornelius]

I will return to this thread in 6 months if the case is still going. >@@(*&)

[John]

So why didn't Eddie alert at any of those places where it is obvious that many people must have bled at some time or another over the years.      It doesn't make sense unless Grime was lying about his dog's skills -  and I don't believe he was.

You agreed that it wasn't feasible that not a speck of blood had ever been shed in the other apartments or cars. So why didn't Eddie alert?

That's pretty easy to answer Benice, it's all to do with quality and quantity.  The dogs will only react where they detect a scent, if the blood has been cleaned away or bleached there will be nothing to find.  If the blood droplet is too miniscule then even Keela or Eddie might not find it, they might have been good but they weren't infallible. 

What was evident however is that the dogs demeanour changed immediately he entered 5a which to an experienced handler like Martin Grime meant only one thing.

[pegasus]

Here's a hypothetical question. On 31 July what if not just 1 EVRD but 5 had checked that apartment (each EVRD seperately of course). Would all 5 have signalled? Or just 1 out of 5? 

[Mr Gray]

again so its on the correct thread...does anyone claim that eddie has never been wrong

[Mr Gray]

Gerry stated that the cadaver dogs are extremely unreliable..posters have claimed that eddie is 100% reliable but have provided no proof..in fact it can't be proved...so how reliable are the dogs....does anyone really know...is there any evidence... I would say NO

[John]

Gerry stated that the cadaver dogs are extremely unreliable..posters have claimed that eddie is 100% reliable but have provided no proof..in fact it can't be proved...so how reliable are the dogs....does anyone really know...is there any evidence... I would say NO

Nobody will ever know how reliable dogs are since failures are not always recognised as such.  Testing dogs in a controlled environment is one thing but working out in the field is a completely different matter. 

[John]

Here's a hypothetical question. On 31 July what if not just 1 EVRD but 5 had checked that apartment (each EVRD seperately of course). Would all 5 have signalled? Or just 1 out of 5?

An excellent point Pegasus     Even using two EVRD's together would have done away with many of the issues we have already considered as troublesome.

[Victoria]

Here's a hypothetical question. On 31 July what if not just 1 EVRD but 5 had checked that apartment (each EVRD seperately of course). Would all 5 have signalled? Or just 1 out of 5?

I would also add, in that scenario I would want each dog to have a unique handler, to be fully satisfied with the results. Even then, if all dogs did alert, we can't actually know what they are alerting to, merely that the strong likelihood is that they are alerting to something.

[Brietta]

Apparently scientists with many years experience of working in the 'body farm' in America have developed a means of identifying and isolating the 'scent of death' which they are able to collect and measure scientifically.

A dog detects air-borne bio-markers that decomposition gives off, but Dr. Arpad Vass, a researcher at the facility, is developing a detector that will respond to the same scents that attract cadaver dogs. It's an artificial nose that pulls air through a tube into a spectrometer chamber. This machine will isolate the specific chemicals. Vass hopes to pinpoint single molecules and make the unit portable for police use.
http://uk.search.yahoo.com/search?fr=mcafee&type=A111GB691&p=Vass+worked+at+%E2%80%9CThe+Body+Farm%E2%80%9D

It is at the stage where their technique is ready to be used and the findings presented as evidence in American courts but I don't know if it has been or not because introduction of it is hotly disputed.
I don't know how typical the Casey Anthony case might be as I believe the smell of decomposition was obvious to the human nose let alone a dog's or scientific measurement.

The prosecution want to submit a report, prepared by Arpad Vass, from Oakridge National Laboratory in Tennessee, which concludes that the air sample contains the key chemical compounds of human decomposition, as well as a large concentration of chloroform. Some media reports are even suggesting that the jury might be asked to smell a can of the air in court.


If the evidence is accepted, it will be the first time an expert witness has been called upon to identify the smell of a decomposing body, although other odour samples have been used in trials in the past, says Christopher Slobogin from Vanderbilt University Law School in Nashville, Tennessee.
http://www.newscientist.com/article/dn20487-casey-anthony-trial-is-the-smell-of-death-evidence.html#.U28jYih7-4c

[Mr Gray]

Nobody will ever know how reliable dogs are since failures are not always recognised as such.  Testing dogs in a controlled environment is one thing but working out in the field is a completely different matter.

John of course is absolutely right and makes a statement that no one can argue with. We simply do not know how reliable the dogs are and therefore to claim a 100% record is absolutely ludicrous. What we do know is that the dogs are very good at finding cadavers and that's why they are being brought in...but is every alert significant...Grime says no

[stephen25000]

John of course is absolutely right and makes a statement that no one can argue with. We simply do not know how reliable the dogs are and therefore to claim a 100% record is absolutely ludicrous. What we do know is that the dogs are very good at finding cadavers and that's why they are being brought in...but is every alert significant...Grime says no

Did he at ant time say the alert wasn't significant in this case ?

[Mr Gray]

Did he at ant time say the alert wasn't significant in this case ?

Grime did not confirm any of the alerts..he says they are suggestive...that's all they are

[stephen25000]

Grime did not confirm any of the alerts..he says they are suggestive...that's all they are

i.e. No he didn't.