The child pornography accusations against former Subway spokesman Jared Fogel have sparked a mix of commentary, sensational headlines, and crass, distasteful jokes about prison rape. For the most part, I’ve been avoiding the whole thing as best I can, especially since I was only marginally aware of Fogle before this whole thing blew up.

However, one interesting dog-related angle has cropped up: Part of the police investigation involved using Bear, a black Lab trained to sniff out electronic devices, in Fogle’s home.

Bear is almost unique; there are only two other dogs with his skill in the entire country. In a profile of the dog last month by Indianapolis station WTTV, Chief Handler Todd Jordan said, “Bear is unique because he can sniff out SD cards, thumb drives, external hard drives, iPads and micro SD cards… It’s something we probably can’t smell.”

It’s almost impossible not to be fascinated by Bear’s abilities, and the charges against Fogle make it easy to cheer him on. But before we start trying to expand the roles of dogs in law enforcement, we should probably take a deep, sober look at the problems involved.

The primary uses of sniffer dogs in law enforcement are to find drugs and explosives. While both of those might sound like noble goals at first glance, there are some very persistent problems with them that have yet to solved.

The first one is constitutional: At what point is it permissible to use a drug-sniffing dog to search a person’s car or home? Does a dog’s response alone constitute probable cause for officers to perform a warrantless search?

This question came before the Supreme Court last year in a case called Florida vs Jardines. In 2006, Police officers brought a drug-sniffing dog to the door of Joelis Jardines’s house, and the dog gave a positive response for drugs. The police pulled almost 180 marijuana plants out of the house. But was the sniffing by the dog a violation of Fourth Amendment protections against unreasonable search and seizure? The court decided that in this case, the answer was yes.

The majority opinion was delivered by Antonin Scalia, who wrote:

[I]ntroducing a trained police dog to explore the area around the home in hopes of discovering incriminating evidence is something else. There is no customary invitation to do that. An invitation to engage in canine forensic investigation assuredly does not inhere in the very act of hanging a knocker. To find a visitor knocking on the door is routine (even if sometimes unwelcome); to spot that same visitor exploring the front path with a metal detector, or marching his bloodhound into the garden before saying hello and asking permission, would inspire most of us to — well, call the police. The scope of a license — express or implied — is limited not only to a particular area but also to a specific purpose.

Some people may roll their eyes at the very idea of the case, especially because Jardines was in fact holding marijuana with an estimated value of $700,000. He was guilty, so many may see his case as being an exploitation of bureaucracy.

But that brings us to the second, more serious problem with drug-sniffing dogs: They aren’t reliable in their abilities. Multiple studies have shown that police dogs strongly respond to the cues — conscious or subconscious — of their handlers. If the handler wants to find drugs, the dog is going to want to please them, especially because giving a positive result often means a reward for the dog. That means that there’s a lot of false positives.

This problem came to the forefront when the case U.S. vs Bentley was decided by the 7th Circuit Federal Appeals Court. Larry Bentley was sentenced to 20 years in prison for possession of cocaine on the basis of a search triggered by Lex, a Belgian Malnois trained to find drugs. However, like many police dogs, Lex is far from accurate. In the field, Lex indicates the presence of drugs about 93 percent of the time, but drugs have been found in only 59 percent of those cases. In other words, as Washington Post columnist Radley Balko points out, Lex is only slightly more accurate as flipping a coin. Even worse, Lex isn’t even the worst example. Balko writes:

Moreover, the court notes that the U.S. Court of Appeals for the Fourth Circuit gave its okay to a dog with a success rate of 43 percent, or less accurate than a coin flip. This even lower number jibes with a 2011 Chicago Tribune investigation of suburban Chicago police dogs that found a success rate of just 44 percent. That review also found that with Latino drivers, the accuracy rate plunged to just 27 percent, more evidence that the dogs are merely reflecting the biases and presuppositions of their handlers. Other studies have shown false positive rates of up to 80 percent. With success rates that low, it’s hard not to conclude that drug dogs aren’t tools to determine probable cause, but basically a “search warrant on a leash.”

Despite the fact that Lex’s rate of failure was established and acknowledged, the Court allowed the search — and Bentley’s conviction — to stand.

We like to think of dogs as being reliably objective, free of the bigotries and conflicted interests of human beings, but obviously they’re not. Like so much else, they learn them from us and act on them.

Dogs certainly aren’t the only animals who are subject to this. YouTube commentator Rebecca Watson has a great video in which she compares police dogs to the case of Clever Hans. Hans was a horse who became a sensation in Europe during the early 20th century because he appeared to be able to solve complex math problems and gave the answer by stomping his hoof. It turned out that like Lex, Hans was only looking for cues of human approval.

But Hans was only an amusement. At most, some people may have lost some money. If police dogs fail at high rates, we’re likely to lose our privacy and our liberties. Are you really willing to have your car or your home searched on the basis of a coin flip?

As I said at the beginning, Bear’s ability to sniff out electronics is a truly amazing thing. But before we use him or other dogs more broadly, a strong sense of realistic skepticism is healthy for all involved.

Via WTTV, Skepchick, and Washington Post

Read more about dogs on Dogster:

• A Waitress Confronts Customers Who Left Their Dog in a Hot Car and Gets Fired for It
• Questions About Foreign Objects in Pedigree Dog Foods Aren’t Going Away
• A Dog Named Pinky Was Left at a Shelter Because of Fleas