It's widely accepted that people who witnessed a crime after having a few drinks tend to be unreliable sources of information. And until recently, the same was assumed of people who had consumed cannabis. However, a new study suggests this isn't true.
A group of researchers from Vrije Universiteit Amsterdam and Florida International University took to a coffee shop in Amsterdam to evaluate exactly how consuming cannabis affected our memory recall. They recruited 120 participants—half of which were assumed to be sober—and put them through a series of memory tests.
The study participants were shown a two-minute video of a convenience store robbery, then asked to recall as many details about the video as they could. While the study states that the intoxicated participants "reported significantly fewer correct detail[s] than did sober participants," this is more a matter of quality over quantity. It's not that the high participants were wrong more often than the sober ones. They simply remembered less details.
After this the participants were asked to identify the culprits from the video from a lineup of suspects. In this test, the participants that had consumed marijuana were just as likely to identify the culprit as those who were sober. In fact, the cannabis consumers tended to report a higher rate of confidence in their decision then their sober counter parts as well.
"The level of confidence expressed in a lineup identification can have a significant impact on judgments about the credibility of the eyewitness and the likely guilt of the suspect," the researchers wrote. "This finding is not in line with the hypothesis that intoxicated participants would compensate for anticipated poorer performance by adjusting their confidence ratings downward."
Across the four tests the researchers conducted, cannabis consumers by and large performed just as well as their sober counterparts. As the study authors wrote, "cannabis intoxication was not associated with either a decrease in correct identifications or an increase in false alarms."
So, the next time you're having a sesh and 'accidentally' pocket someone else lighter, just remember, smoking weed doesn't make people any easier to dupe.
H/T: Marijuana Moment