Smells can be wonderful: the scent of roses or the freshness of the air that follows a cleansing rain, for example, are loved by many. The human nose really is an impressive instrument. Not only does our sense of smell allow us to detect bacteria and enable us to taste foods fully, but we can also use it to play the real life although not-so-fun game of “find the bad smell in the apartment”.
Yes. It seems that the nose really knows.
Or does it? As much as we rely on it every day or our lives, researchers have learned that humans do not fare that well when it comes to reliably detecting and properly identifying odors, foul or otherwise. Random smells can be confusing, and can lead to serious consequences for those deemed to be responsible for odors such as burning cannabis.
The 4th Amendment of the US Constitution protects US citizens against unreasonable search and seizure. In other words, without a good cause, an officer cannot randomly pick you out of a crowd and strip search you. However, probable cause can be met if an officer claims that they that they smelled pot. This is why countless searches have been carried out when there was no other tangible evidence of wrongdoing. It can apply in other situations as well, as a recent case demonstrated.
Suspended Without Cause, By Those Without a Clue
A North Carolina school recently suspended a student for smelling like weed, even though she passed a drug test and no marijuana was found in her possession. Simply being accused of an infraction was enough ‘evidence’ to be judged guilty and swiftly punished. To make matters worse, the suspension form did not include a check box for “odd odors” as a reason for punishment, and so the school authorities checked “possession” and handed out a five-day suspension. The student missed three tests and had to complete a lot of makeup work, and was unable to appeal the school’s decision to a higher authority.
All of this occurred because, in their untested and unchallenged opinion, the school authorities thought the student smelled like pot. The story was leaked to the news, causing the school to face some backlash; the school in question, however, does not deem their process to be flawed as of the writing of this article.
Instead, they have fallen back on the old standby that their teachers had justification because of what they thought they smelled and who they believed to be the source. It is noteworthy that the student in question also happened to be African American.
Probable Cause: Where There’s Smoke, There Must Be Fire?
People of color are often the hardest hit by such tactics when facing accusations of wrongdoing, and are six times more likely to be suspended from school than their white counterparts. Sadly, this kind of thing happens all the time, but more often than not, the consequences are far worse than a few days of suspension from school. False or unsubstantiated cannabis charges can result in costly fines, losing a job, or even imprisonment. Additionally, although studies have indicated that black people are no more likely to smoke pot than white people, they are 3.7 times more likely to be arrested for it.
To add insult to injury, the poor are the most vulnerable: they are more likely to be convicted simply because they lack access to qualified legal counsel, and have to rely on overworked and underpaid public defenders who are more likely to encourage them to plead out, even if they are innocent.
Which brings us again to the original question…
Can Humans Reliably Detect the Smell of Pot?
The assertion that humans can be counted on to reliably detect cannabis odors has, for the most part, gone unchallenged because everyone just assumed it was true. But is it?
Well, apparently, not so much. Researchers recreated real-world scenarios based on actual court cases involving the ability to detect the odor of marijuana.
The results, published in Law and Human Behavior in April of 2004, determined that people did not fare well in identifying cannabis odors. Even though participants believed that they had an excellent sense of smell, when they were tested, they failed miserably. You may argue that officers receive special training that helps them recognize the scent of marijuana. This may be true to some degree, but the study participants were provided samples of cannabis in order to teach them, so they could presumably be able to pass the tests.
However, even after training, the participants failed. They frequently reported that a bag had the smell of marijuana even when none was present. They also failed to detect cannabis in the control bag that actually did contain it.
Other scenarios were tested based on real cases. In one such trial, a 1983 Chevrolet’s closed trunk held a specified amount of marijuana for a specific time span based on court records. The officer had stated that he could smell the stored cannabis through the open driver’s side window. The participants were placed in the exact same spot and tested in the identical conditions.
Once again, six out of nine participants got it wrong. In fact, out of fifty-four trials, they gave a significant number of false positives and failed to detect the odors correctly when cannabis was present.
Another experiment focused on the odors associated with growing weed. The majority of the participants once again failed to detect growing marijuana, and stated that they did smell it when it was not present. The upshot is that while further research is required (studies need to be replicated to be scientifically relevant), testing has shown that people cannot accurately detect marijuana and often make mistakes in determining if pot is or is not present.
As more and more states decriminalize marijuana, law enforcement is having to adapt. In Washington DC, this is already evident as internal affairs cases are skyrocketing. Since pot is now legal, the ability to defend search and seizure on the grounds of smelling cannabis has gone up, although certain arrests are down.
Long story short: the nose is not as reliable as we like to think, and probable cause may be going up like a puff of smoke.