I read something relating to heat detection devices being dismissed as unreliable, as they also flagged legitimate legal heating sources, thus nullifying probable cause. I understand that the dog will ONLY trigger with illegal activity.

I dislike the notion that Joe Copper can run a K-9 unit up to my door for no reason at all, and let the dog sniff search my domicile to establish probable cause so he can do a search. I would assume there was a reason that this Joe Copper pulled that dog up to THAT particular door. I'm just saying if you don't have enough to do a search warrant, you should probably not be allowed to bring scanning/searching equipment up to a domicile and "check it out". That for me, includes sniffing dogs.

Here's the affidavit submitted in support of the warrant:

“Your Affiant's† reasons for the belief that “The Premises† is being used as [a marijuana hydroponics grow lab] and that “The Property [consisting of marijuana and the equipment to grow it]† listed above is being concealed and stored at “The Premises† is as follows:
On November 3, 2006, “Your Affiant† detective William Pedraja, # 1268, received information from a crime stoppers tip that marijuana was being grown at the described residence.
On December 5, 2006, “Your Affiant† conducted surveillance at the residence and observed no vehicles in the driveway. “Your Affiant† also observed windows with the blinds closed. “Your Affiant† and Detective Doug Bartelt with K–9 drug detection dog “FRANKY† approached “The Premises† in an attempt to obtain a consent to search. While at front door [sic], “Your Affiant† detected the smell of live marijuana plants emanating from the front door of “The Premises.† The scent of live marijuana is a unique and distinctive odor unlike any other odor. Additionally, K–9 drug detection dog “FRANKY† did alert to the odor of one of the controlled substances he is trained to detect. “Your Affiant,† in an attempt to obtain a written consent to search, knocked on the front door of “The Premises† without response. “Your Affiant† also heard an air conditioning unit on the west side of the residence continuously running without recycling. The combination of these factors is indicative of marijuana cultivation.
Based upon the positive alert by narcotics detector dog “FRANKY† to the odor of one or more of the controlled substances that she is trained to detect and “FRANKY† [sic] substantial training, certification, and past reliability in the field in detecting those controlled substances, it is reasonable to believe that one or more of those controlled substances are present within the area alerted to by “FRANKY.† Narcotics Canine handler, Detective Bartelt, Badge number 4444, has been a police officer with the Miami–Dade Police Department for nine years. He has been assigned to the Narcotics Bureau for six years and has been a canine handler since May 2004. In the period of time he has been with the Department, he has participated in over six hundred controlled substances searches. He has attended the following training and received certification as a canine handler....
Since becoming a team, Detective Bartelt and narcotics detector canine “FRANKY† have received weekly maintenance training.... Narcotics detector canine “FRANKY† is trained to detect the odor of narcotics emanating from the following controlled substances to wit: marijuana .... To date, narcotics detector canine “FRANKY† has worked approximately 656 narcotics detection tasks in the field. He has positively alerted to the odor of narcotics approximately 399 times. “FRANKY'S† positive alerts have resulted in the detection and seizure of approximately 13,008 grams of cocaine, 2,638 grams of heroin, 180 grams of methamphetamine, 936,614 grams of marijuana, both processed ready for sale and/or live growing marijuana.
WHEREFORE, Affiant prays that a Search Warrant be issued ... to search “The Premises† above-described....


The case does make reference to the thermal imaging case.  The US Supreme Court did outlaw use of these devises in 2001 (after I graduated law school, so I don't feel as bad missing that) and actually relied on that case to some extent.  The dissent (it was a 5-2 decision) relied on other dog-sniffing cases to conclude that the dog approaching your door and sniffing air on the porch isn't a search.

Having read the case makes this a potentially interesting Supreme Court case.  The Supreme Court tends to be big on not changing precedent.  They have 3 published dog-sniffing cases, all of which concluded a sniff by a dog isn't a search.  Since the 4th Amendment protects against unreasonable searches, if the police conduct isn't a search, there cannot be a violation.  The distinction in the thermal imaging case was that a thermal imaging device could mistake otherwise lawful activity (the example the use was owning a hot tub) for unlawful activity.  However, they reasoned that the dog didn't have the same risk because it only alerts on illegal activity.  Very interesting stuff.

Also I would have assume this to be an illegal search on scene. 

Fors, as to your comment on the supreme courts conservative majority, I think that could factor opposite of what you think.  I know conservatives normally favor law enforcement but conservatives also normally favor the bill of rights.  Houses have always been seen as ultimate sanctuaries.  Right or wrong what is done behind closed doors takes a warrent to look at.  Three exceptions apply.  Exigent circumstances (evidence being destroyed), hot pursuit (chasing a felony) and public care taker (believe someone is in danger).  I dont see how any of these apply.