Warrant-less searches using sniffing dogs : What if items the dog couldn't smell are found?

Probable cause is not a scientific concept. The presence or absence of probable cause is not determined by exacting analysis on the part of a legal technician. Probable cause exists when the facts and circumstances of which he has generally reliable information are sufficient to cause a person of reasonable caution to believe that it’s generally likely that an offense has been or is being committed.

Reminds me of the joke about how the vaious professions prove all odd numbers are prime:

Mathematician - "1 is prime, 3=1+2 is prime, 5=3+2 is prime, 7=5+2 is prime… therefore by induction, all odd numbers are prime.

Physicist - “1 is prime, 3 is prime, 5 is prime, 7 is prime, 9 - experimental error, 11 is prime… I conclude all odd number are prime.”

Engineer - “1 is prime, 3 is prime, 5 is prime, 7 is prime, 9 is prime, 11 is prime… so all odd number are prime.”

(My brother the engineer did not like the punch line…)

Accountant - “Which numbers do you want to be prime?”

I agree with your entire statement. However if these “facts and circumstances” are based on bogus science, then they by definition are not “sufficient to cause a person of reasonable caution” to conclude that there exists a possibility of crime anymore than using a dowsing rod.

You would agree that if by flipping a coin, heads I search and tails I do not search, that in 44% of cases I find drugs when I search, that is not valid probable cause? Even if 100% of the time it came up heads I found drugs, it is still not probable cause, right?

That is because there is no correlation between the outcome of the coin flip and the finding of drugs.

Would you agree that if the dog sniffs were shown to be junk science then they could not support probable cause, even if they were “right” a sufficiently non-zero percent of the time?

Not sure I know what “junk science,” means in this context.

If controlled studies showed no correlation between dog alerts and the presence of drug odor, I’d agree. But the study could not simply rely on field results – the inability to find drugs doesn’t eliminate the case that drug odors were in fact present.

So I’d be looking to see a legitimate double-blind study that disproved correlation between dog alerts and drug odors.