We have previously written about the problems with eyewitness testimony when it comes to accurately prosecuting anything from drug charges to sex crimes to simple shoplifting. The problem is that human memory and observational abilities are extremely fallible, yet eyewitness testimony often proves very convincing in court.
This has led to countless wrongful convictions over the years, some of which resulted in a lifetime of wrongful imprisonment. According to the results of a recent study, the memory of police officers is often just as fallible as that of average citizens, especially after a short burst of extreme bodily exertion such as a foot chase or physical altercation.
Researchers tested 52 police officers who were all in good shape and had about eight years of experience. As part of the test, all officers were given information about a criminal scenario involving a string of armed robberies. They were also shown photos of six suspects.
All officers also went through a scenario where they engaged in a heated verbal encounter with a "target individual" in a simulated home environment.
However, before that encounter, half the officers were asked to tire themselves out by hitting a punching bag. The other half of the group did not exert themselves.
Then it was time for memory tests. When all was said and done, the officers in the exertion group remembered far fewer details about the encounter or the information they had received in the briefing.
When it comes to making arrests, officers may find themselves chasing down a suspect or fending off an assault. The results of this study show that these activities can blur memories and make subsequent police testimony very inaccurate and vague.
The study's lead author explained: "As exhaustion takes over, cognitive resources tend to diminish. The ability to fully shift attention is inhibited, so even potentially relevant information might not be attended to. Ultimately, memory is determined by what we can process and attend to."
Hopefully, study results like these will force prosecutors and law enforcement to seek out evidence that is far more concrete and consistent than simple police officer observation. When a defendant's very freedom is at stake, it is unjust to rely solely on something as flimsy and malleable as human memory.
Source: CNN Health, "Cops more forgetful after chases or altercations," Saundra Young, Mar. 20, 2012