Who let the dogs in?

Jacob Sullum has a nice recap of the Illinois v. Caballes Supreme Court ruling.
It’s been heartening to see the amount of negative reaction to the ruling around the web. At the same time, it was depressing to hear two local police chiefs on the radio gleefully talk about how this frees them up to really start using the drug dogs.
After reading the decision again, I am even more convinced that this is going to end up haunting Justice Stevens. It’s poorly written, and it’s bad law.
Oh, and just a note for those who favor drug-sniffing dogs because they see a dual purpose of watching out for terrorists smuggling in explosives, it doesn’t work that way. As Jackl reminded me:

One thing about dawgs ya’ll ought to know: a scent dog is either a drug dog or a bomb-sniffing dog, but not both: See, K9 Units in Public Transportation: A Guide for Decision Makers (pdf, p. 52) (National Research Council).

Specialty K9s are never trained in both explosives and narcotics detection. K9 trainers
refer to this combination as dangerous training, meaning that it dulls the capabilities of
the K9 to perform effectively at either specialty.

So every dog that is trained as a drug sniffing dog is one that is not trained to detect explosives.