A teenage boy has been slain, riddled with bullets during a drive-by shooting, and there, on the witness stand, is his crying mother. She's understandably weeping, wracked by the senseless killing of her darling son. Even worse, she witnessed it all.
"Ma'am, is the man who murdered your son present here today?" the prosecutor questions.
Through the tears, streaming freely, their flow rekindled from having to relive and recount such a horrible event, she manages a nod.
"Can you point him out for us?"
A pause, followed by emphatic pointing at the defendant.
"That's the man! He killed my baby!"
Eyewitness testimony has been a central facet of the American judicial system for centuries. Spirited, dramatic exchanges between attorney and witness are what draw us to courtroom dramas and news stories about pretty women who murder their boyfriends.
There's scant evidence more damning than the sworn statement of a bereaved mother who firmly asserts the guilt of the defendant, especially if such evidence is corroborated by other eyewitnesses.
But eyewitness testimony is merely the product of human memory, and decades of scientific evidence have demonstrated that memory is glaringly fallible.
"All our memories are reconstructed memories," forensic psychologist Scott Fraser explained at TEDxUSC last May. "They are the product of what we originally experienced and everything that's happened afterwards. They're dynamic. They're malleable. They're volatile..."
And they can easily be corrupted. According to Fraser:
"Under the best of observation conditions, the absolute best, we only detect, encode and store in our brains bits and pieces of the entire experience in front of us... So now, when it's important for us to be able to recall what it was that we experienced, we have an incomplete [memory], and what happens? ...The brain fills in information that was not there, not originally stored, from inference, from speculation, from sources of information that came to you, as the observer, after the observation. But it happens without awareness such that you... aren't even cognizant of it occurring."
Since 1992, The Innocence Project has exonerated 306 innocent individuals who were mistakenly convicted of a crime. In three-quarters of these cases, incorrect eyewitness testimony sent those people to prison, by far and away the most common reason. What's startling is that in the vast majority of these cases, witnesses weren't lying. They profoundly and genuinely believed that the people they accused were the perpetrators of the crimes.This can happen for a lot of reasons. For one, crimes are often emotional and traumatic experiences, and such emotion can have a marked effect on memory. In a study published in February, University of Texas psychologists found that subjects who viewed a video of a mugging were able to recall the event and describe the perpetrator more vividly than subjects who simply watched a video of a conversation, providing more details and ascribing more certainty to their descriptions.
However, in a second experiment, the researchers found that vividness did not correlate with accurate recall. Subjects who witnessed the crime were less able than subjects who watched a conversation to recognize the people involved from a photographic lineup.
False memories can also arise throughout the judicial process. Investigators can easily influence -- intentionally or unintentionally -- the memory of eyewitnesses. Rudimentary verbal or nonverbal affirmations can cause witnesses to become surer of their memories. Suggestive questions by prosecutors can lead to the emergence of novel, erroneous details in witnesses' memories, and cause witnesses to "recall" events that may have never actually happened.
The key, Fraser reminds us, is to be cautious. "The accuracy of our memories is not measured in how vivid they are nor how certain you are that they're correct," he said.
But we can do more than simply be vigilant of our memory's shortcomings. Given its fallibility, one could go so far as to argue that limits should be placed on eyewitness testimony. Perhaps it should be restricted in cases where forensic analysts can determine that vision was hindered, such as in crowds or at night? Maybe more than one eyewitness should be required for such testimony to be allowed in court? Maybe eyewitness accounts should be disallowed altogether in capital trials?
One simple action that can be taken is to mandate double-blind lineups in police stations. This means that the investigator conducting a photo or live lineup will not be aware of who the suspect is. That way, he or she won't be able to influence the witness, knowingly or unknowingly.
We would also be wise to follow New Jersey's example. There, judges are now required to inform juries that "certain factors about an eyewitness's circumstances at time of the offense could render the testimony less reliable. Those factors include the stress the eyewitness was under, the duration of the event, lighting, distance, the eyewitness's focus on a weapon, and cross-racial identification."
Such a basic reminder is undeniably warranted. In a 2011 nationwide survey of 1,838 individuals, 37.1% of respondents were found to believe that "the testimony of one confident eyewitness should be enough evidence to convict a defendant of a crime."
Such thinking is clearly faulty. The truth is not what somebody believes it to be, no matter how adamantly they swear it to be so. Our court system must be insulated from the fallibility of memory.
(Image: Swearing in a Witness via Shutterstock)
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Redheads, such as the awesomely hilarious Conan O'Brien (as well as the less-than-awesome Carrot Top) have a lot of pheomelanin. This gives him his characteristic red hair, and as Conan frequently points out, his disturbingly pale skin. For years, scientists believed that pale skin explained why redheads were particularly susceptible to melanoma.
Peering through his telescope in the early 17th century, Italian astronomer Galileo Galilei found Venus to be almost featureless. What he saw was Venus' defining, impenetrable layer of thick clouds, obscuring the surface and shrouding the planet in mystery, a mystery quite open to speculation. As summarized by Carl Sagan in Cosmos, one of the most outlandish, yet surprisingly common lines of speculative reasoning went a little like this:
We now conclusively know that there's no rain on Venus, not even a drizzle. The planet's sizzling environment, sporting temperatures in excess of 800 degrees Fahrenheit, vaporized liquid water long ago. With this knowledge, we can revise the aforementioned line of reasoning to reach a more correct conclusion: 
The typical human being poops about once per day, excreting approximately one ounce of waste for every twelve pounds of body weight. If the lifetime fruits of this regular labor were gathered and piled, the typical American would own a stinky mound weighing almost 27,000 pounds!
Silver stools are shocking, but even more eye-opening (and unpalatable) is what comes out of the butts of newborn human babies. Surprise: it's actually not feces! Composed of the materials ingested by the baby from its time spent in the uterus -- often epithelial cells, mucus, amniotic fluid, and bile -- the substance is called meconium. Meconium has the sticky texture of tar, is olive green in hue, and is thankfully odorless. The same cannot be said for infants' later stools, however.
In 1927, the pioneering forensic scientist Alexander Gettler, a toxicologist for the City of New York, reported that in the previous year 1,200 New Yorkers had been sickened or blinded by the government's poisoned alcohol, and another 400 had died. Even before these perturbing statistics came to light, Gettler's boss, the now legendary medical examiner Charles Norris, was already incensed with the Federal Government's actions: 
But that, of course, is not necessarily true. If marriage really were so unpleasant, then far fewer people would be doing it. 
Biologist Jaroslav Flegr, one of the leading researchers on T. gondii has discerned some very peculiar findings when comparing people with the infection to those without it. Kathleen Mcauliffe reported on this last year in The Atlantic:
Since its inception, researchers have been closely monitoring the HuMed program. They've found that the enrolled students are generally just as successful in medical school as their peers.
As shown, men who were taking placebo offered about 50% of their money in the trust game to women of "low attractiveness," while they gave 65% of their money to women of "high attractiveness." Men receiving a regimen of minocycline gave about 50% to both groups of women.
Dumbacher and his colleagues had inadvertently ingested a pernicious neurotoxin called batrachotoxin. When consumed, the toxin adversely interacts with nerve cells by keeping their voltage-gated sodium channels open. This means that muscle and brain cells can't generate an ion potential and fire like they're supposed to. In low doses, the toxin merely renders nerves and muscles inoperable, but in higher doses, it can actually cause paralysis and inhibit one's ability to breathe, potentially resulting in death.
So what would life resemble instead? 
The two astrophysicists also dreamed of another life form: "hunters." Winged, faster, and more maneuverable, they would nip and peck at the much larger floaters to sustain themselves.