Poll - Scent Dogs Accuracy

[Robittybob1]

Dogs trained to react to blood will do so.

But not otherwise.

Ditto dogs trained to react to drugs.

Or trained to react to explosives.

Or trained  to react to cancer cells in humans.

But in each of the above-listed cases, not otherwise.

But there is no reason you can't have a dog trained in detecting two groups of items, eg drugs and explosives at border controls.  (Think of the range of drugs there are and I not sure but I'd imagine explosives will have various odours as well.)

[ferryman]

But there is no reason you can't have a dog trained in detecting two groups of items, eg drugs and explosives at border controls.  (Think of the range of drugs there are and I not sure but I'd imagine explosives will have various odours as well.)

Eddie was dual-trained to react to blood and (other) scents of dead humans.

Of course, blood can be shed by living people.

The key point, though.

If you have one dog trained to react to blood and ....

Why Keela (trained to react to nothing else)?

[pathfinder73]

Dogs trained to react to blood will do so.

But not otherwise.

Ditto dogs trained to react to drugs.

Or trained to react to explosives.

Or trained  to react to cancer cells in humans.

But in each of the above-listed cases, not otherwise.

Cadaver dogs will alert to human blood on its own. Go ask an expert if you don't believe it's true?

"Training a cadaver dog requires regular contact with human blood, decaying flesh and bones. In the United States, dog handlers can legally obtain bodily components like human placenta and blood, but not always easily, and trainers like Cablk often resort to using their own blood."
https://www.nytimes.com/2015/06/21/magazine/how-to-train-a-cadaver-dog.html

[Robittybob1]

Eddie was dual-trained to react to blood and (other) scents of dead humans.

Of course, blood can be shed by living people.

The key point, though.

If you have one dog trained to react to blood and ....

Why Keela (trained to react to nothing else)?

Eddie just barked in the general region of the odour e.g. was it the wardrobe or just the corner of the room?
Whereas Keela had the sense to point to the exact spot where the sample has to be taken from.

[ferryman]

Cadaver dogs will alert to human blood on its own. Go ask an expert if you don't believe it's true?

"Training a cadaver dog requires regular contact with human blood, decaying flesh and bones. In the United States, dog handlers can legally obtain bodily components like human placenta and blood, but not always easily, and trainers like Cablk often resort to using their own blood."
https://www.nytimes.com/2015/06/21/magazine/how-to-train-a-cadaver-dog.html

From your link:

In the United States, dog handlers can legally obtain bodily components like human placenta and blood, but not always easily, and trainers like Cablk often resort to using their own blood.

You introduce the dog to blood to unlock its ability to find it.

[slartibartfast]

Eddie was dual-trained to react to blood and (other) scents of dead humans.

Of course, blood can be shed by living people.

The key point, though.

If you have one dog trained to react to blood and ....

Why Keela (trained to react to nothing else)?

It's called logic.

[ferryman]

It's called logic.

Not to train your cadaver dog to react to blood if you have another dog trained to react to nothing but.

Yes.

[John]

Not to train your cadaver dog to react to blood if you have another dog trained to react to nothing but.

Yes.

Had there been a dog trained to detect only cadaver odour then that dog could have been deployed instead of Eddie.

[pathfinder73]

Cadaver dogs led them to the spot on the 90-acre farm in Solebury Township where they discovered human remains inside a 12ft-deep common grave.

“I don’t understand the science behind it, but those dogs could smell these poor boys 12-and-a-half-feet below the ground,” the Bucks County district attorney Matthew Weintraub said at a midnight news conference.

https://www.theguardian.com/us-news/2017/jul/13/pennsylvania-missing-men-body-found?CMP=twt_gu

3:48

[ShiningInLuz]

http://www.bbc.com/news/world-us-canada-40740503

A missing woman in Florida, who suffers from dementia, was found rapidly by a sniffer dog after the animal was provided with an armpit scent pad sample taken and bottled two and a half years ago.

The dog got an ice-cream as its reward.   

[Brietta]

http://www.bbc.com/news/world-us-canada-40740503

A missing woman in Florida, who suffers from dementia, was found rapidly by a sniffer dog after the animal was provided with an armpit scent pad sample taken and bottled two and a half years ago.

The dog got an ice-cream as its reward.   

Searching for vulnerable people who have wandered off and get lost as a result is one of the tasks undertaken on a regular basis by police search and rescue and cadaver dogs.

I've never heard of it before but like all the best ideas storing scent for emergency use is just so logical it is amazing we don't do it as a matter of course.  It should work for children and although in a domestic setting there should be plenty of trace around it could be almost guaranteed to be specific if isolated in a bottle.

Snip
Manufacturers say they work better and more quickly than articles of clothing, because they are not contaminated by other people's smells or smells from the environment.

[pathfinder73]

[misty]

Whilst searching for some answers to a particular live-scent dog related issue, I came across an interesting case in the USA which has historical parallels to the McCann case (dog alerts, eye-witness testimony & partial tangible evidence match) - State of Florida v Wilton Dedge.
http://scholarship.law.upenn.edu/cgi/viewcontent.cgi?article=1092&context=jlasc

It's a long read but well worth the time spent when considering scent dog evidence, handler claims & also eye witness testimony.

Wilton Dedge was the accused, Ms. Smith the rape victim.

*snipped*
The only other “evidence” that the police were able to develop before trial involved the
use of a scent dog months after the crime. In March 1982, Dedge wet his hands in the Brevard
County Courthouse bathroom, dried them on paper towels from a bathroom dispenser, and handed
the paper towels to an investigator. The investigator grasped the paper towels by the edges, hung
them to dry, and then placed them in a paper bag from a coffee shop in the building.34 Eight days
later, police dog handler John Preston and his German shepherd, Harrass II, conducted a “scent
lineup” using the sheets from Ms. Smith’s bedroom and four dirty sheets from the local jail that
Dedge had never touched. Harrass II sniffed the dried, eight-day-old paper towels in the bag and
Preston walked the canine up and down the lineup of sheets, commanding him to “search.” On the
second pass, Harrass II stopped at the (bloody) sheet from Ms. Smith’s bed, allegedly detecting
Mr. Dedge’s scent on the sheet—more than three months after the crime. Harrass II was later brought to Ms. Smith’s home, where he supposedly indicated Dedge’s presence more than three
months earlier by touching his nose to various areas in the house.
The trial began in September 1982 and lasted eight days. The State relied upon three
things to prove Dedge’s guilt  1) the eyewitness testimony of Ms. Smith; 2) the hair analysis; and
3) the dog scent lineup.

Dedge was found guilty & had his sentence increased to life after a prison inmate falsely snitched to obtain a reduced sentence for himself.
To cut a long story short, Dedge was eventually cleared years & multiple appeals later, after 2 sets of DNA tests were carried out on semen traces collected from the victim at the time.
The dog handler in question, John Preston, was later discredited but reportedly helped secure convictions in around 100 cases across the US. https://en.wikipedia.org/wiki/John_Preston_(dog_handler)

It poses the question to the Dogs Don't Lie Brigade - was the handler to blame, or the dog, for all the false alerts?

[Mr Gray]

Whilst searching for some answers to a particular live-scent dog related issue, I came across an interesting case in the USA which has historical parallels to the McCann case (dog alerts, eye-witness testimony & partial tangible evidence match) - State of Florida v Wilton Dedge.
http://scholarship.law.upenn.edu/cgi/viewcontent.cgi?article=1092&context=jlasc

It's a long read but well worth the time spent when considering scent dog evidence, handler claims & also eye witness testimony.

Wilton Dedge was the accused, Ms. Smith the rape victim.

*snipped*
The only other “evidence” that the police were able to develop before trial involved the
use of a scent dog months after the crime. In March 1982, Dedge wet his hands in the Brevard
County Courthouse bathroom, dried them on paper towels from a bathroom dispenser, and handed
the paper towels to an investigator. The investigator grasped the paper towels by the edges, hung
them to dry, and then placed them in a paper bag from a coffee shop in the building.34 Eight days
later, police dog handler John Preston and his German shepherd, Harrass II, conducted a “scent
lineup” using the sheets from Ms. Smith’s bedroom and four dirty sheets from the local jail that
Dedge had never touched. Harrass II sniffed the dried, eight-day-old paper towels in the bag and
Preston walked the canine up and down the lineup of sheets, commanding him to “search.” On the
second pass, Harrass II stopped at the (bloody) sheet from Ms. Smith’s bed, allegedly detecting
Mr. Dedge’s scent on the sheet—more than three months after the crime. Harrass II was later brought to Ms. Smith’s home, where he supposedly indicated Dedge’s presence more than three
months earlier by touching his nose to various areas in the house.
The trial began in September 1982 and lasted eight days. The State relied upon three
things to prove Dedge’s guilt  1) the eyewitness testimony of Ms. Smith; 2) the hair analysis; and
3) the dog scent lineup.

Dedge was found guilty & had his sentence increased to life after a prison inmate falsely snitched to obtain a reduced sentence for himself.
To cut a long story short, Dedge was eventually cleared years & multiple appeals later, after 2 sets of DNA tests were carried out on semen traces collected from the victim at the time.
The dog handler in question, John Preston, was later discredited but reportedly helped secure convictions in around 100 cases across the US. https://en.wikipedia.org/wiki/John_Preston_(dog_handler)

It poses the question to the Dogs Don't Lie Brigade - was the handler to blame, or the dog, for all the false alerts?

Grime has coveted himself by never claiming the dogs alerted to cadaver scent...

[misty]

Grime has coveted himself by never claiming the dogs alerted to cadaver scent...

Yet the Portuguese court said it was a fact the dogs had alerted to cadaver scent and we know what that would have meant for the McCanns had they ever been prosecuted.
Dredge was convicted on the basis of incorrect identification by a witness - the actual victim (think Martin Smith), the hair which was very similar to Dredge's & would not rule him out as the attacker (think 15/19 alleles) & the dog alerts which placed him at the crime scene.  If an American jury could be fooled (many times over in Preston's case) so could a smaller number of Portuguese jurors.