Fort Collins, CO: Subjects are unable to identify cannabis when it is packaged in vacuum-sealed plastic, but can do so when it is packaged in resealable sandwich bags, according to data published in the journal Science & Justice.
A team of investigators affiliated with Colorado State University evaluated whether untrained observers could correctly identify dried cannabis flower based solely on smell. They reported, "[O]pen and casually packaged cannabis was identified with high accuracy, while material packaged in doubly vacuum-sealed plastic was correctly identified at rates no different from chance."
Authors concluded: "Interpretation of the plain smell doctrine is complicated in states where possession of a small amount of cannabis, or possession by persons with medical marijuana cards, has been legalized. … Given the results of the present study, smell-based searches where the material was vacuum-sealed within one or more layers of plastic may lie beyond the ‘sphere of reliability.’"
Full text of the study, "Human olfactory detection of packaged marijuana," appears in Science & Justice.