Justice Frankfurter wrote in 1927 that
What is the worth of identification testimony even when uncontradicted? The identification of strangers is proverbially untrustworthy.[1]
During the early 19th century, mistaken identification by eyewitness was widely recognized as the leading cause of wrongful convictions in the U.S.[2] Unfortunately, this trend does not seem to have changed in the last century.
The Innocence Project estimates that of the 349[3] wrongful convictions of defendants it has worked to exonerate, “[e]yewitness misidentification is greatest contributing factor to wrongful convictions proven by DNA testing . . . .”[4] The Supreme Court has recognized the seriousness of the issue, stating that eyewitness misidentification “probably accounts for more miscarriages of justice than any other single factor.”[5]
Yet federal courts’ analyses of eyewitness identification of due process have not been sufficient to protect innocent defendants from wrongful conviction. In Neil v. Bigger, the Court recognized that the primary evil to be avoided is “very substantial likelihood of irreparable misidentification.”[6] Despite this dictum, the Court found that “show-up” identifications can still meet requirements for due process and it rejected a strict exclusion of suggestive identifications. The Court detailed what it factors it viewed as relative to determining if eyewitness identification procedures were adequate to ensure that due process of the criminal defendant was afforded.[7] Unfortunately, these “factors” are not founded in science, and in fact represent many of the lay assumptions about the brain and memory formation, retention and recall.[8]
Courts and laypeople alike tend to perceive of human memory as a straightforward, linear process:[9]
The expectation is that memories are stored like TiVo recordings. and that witnesses can retrieve them at will. That the quality of witness identification and testimony are dependent only on the credibility of the individual offering it. Conversely, neuroscience has shown that eyewitnesses are generally unreliable—due to the complexity and frailty of the brain, racial differences between witnesses and those they identify, stress during memory formation, and other factors.[10] Furthermore, human memory is highly susceptible to external factors, and thus our memories change over time.[11] Despite this unreliability, many jurisdictions do not allow expert testimony on the neuroscience of memory and the unreliability of eyewitness testimony.[12]
Yet the courts have yet to incorporate a nuanced understanding of the human brain—and how the mind is in fact a complex network of independent and overlapping neural processes. Contrary to lay-perceptions, fMRI scans demonstrate that different parts of the brain are responsible for the different “phases” of memory creation:[13]
The fact that various processes and parts of the brain is simply one demonstration that the acts of creating (encoding), keeping (maintenance), and retrieval (remembering) a memory are not identical, and various genetic, physical, and environmental factors can have different effects on these distinct neural processes.[14] Moreover, the type of memory one is attempting to recall employs different parts of the brain and neural processes:[15]
This neuroscience finding directly challenges a common lay perception on memory: that all memories are created equal. In fact, whether you are recalling something you were not paying attention to, compared to something you are familiar with or found novel, it is actually different parts of the brain that activate.[16] Additionally, it has been well-established that memory retention is different for formaiton of short-term memory (STM), immediate-term memory (ITM), anesthesia-resistant memory (ARM), and long-term memory (LTM).[17] The last of which, LTM, is most commonly relied upon in eyewitness identification and requires repetitive mental training and only develops after several hours:[18]
Thus, while the field of neuroscience is expanding its tools and findings, the criminal courtroom has yet to catch up. Potential jurors still typically believe that your mind can play back what you previously experience like a video recording, that your memory is stable over time, that confidence in your memory is correlated to accuracy, that subsequent events do not alter your prior memories, and that people’s faces stand out and can easily be recognized.[19] Yet, the majority of qualified memory experts reject every single one of these statements:[20]
Currently, the “reason most frequently cited by courts for excluding expert testimony is that expert testimony regarding the accuracy of identifications usurps the role of the jury as the sole judge of the credibility of witnesses.”[21] Given the terrifying frequency and centrality of eyewitness identification in wrongful convictions over the last one hundred years, it is time for all jurisdictions to allow scientists to give testimony on the credibility of witnesses’ identification and memory. Only permitting memory expertise in the courtroom will enable jurors to be fully informed when assessing witness credibility.
[1] United States v. Wade, 388 U.S. 218, 228, 87 S. Ct. 1926, 1933, 18 L. Ed. 2d 1149 (1967) (quoting The Case of Sacco and Vanzetti 30 (1927)).
[2] See e.g., Hugo Münsterberg 49–56 (1908); Edwin M. Borchard, Convicting the Innocent at xiii-xv (1932) (early case study finding that forty-four of the studied sixty-five wrongful convictions were based upon mistaken eyewitness identification); see also Joyce W. Lacy and Craig E. L. Stark, The Neuroscience of Memory: Implications for the Courtroom, 14 Nat. R. Neuroscience 649, 649-50 (discussing that empirical research studies have shown how imperfect human memory since 1885, and yet these conclusions have remained largely unrecognized in contemporary society).
[3] Innocence Project, http://www.innocenceproject.org/#causes (last visited Feb. 21, 2017).
[4] Innocence Project, http://www.innocenceproject.org/causes/eyewitness-misidentification (last visited Feb. 21, 2017).
[5] United States v. Wade, 388 U.S. 218, 229 (1967).
[6] Neil v. Biggers, 409 U.S. 188, 198-99 (1972).
[7] Id. at 199-00 (“the factors to be considered in evaluating the likelihood of misidentification include the opportunity of the witness to view the criminal at the time of the crime, the witness’ degree of attention, the accuracy of the witness’ prior description of the criminal, the level of certainty demonstrated by the witness at the confrontation, and the length of time between the crime and the confrontation.”)
[8] Ralph N. Haber & Lyn Haber, Experiencing, Remembering and Reporting Events, 6 Psychol. Pub. Pol’y & L. 1057, 1057-58 (2000).
[9] Saul Mcleod, Stages of Memory Encoding Storage and Retrieval, Simple Psychology (2013) (last visited Aug. 6, 2016), http://www.simplypsychology.org/memory.html.
[10] Alex Kozinski. Criminal Law 2.0, 44 Geo. L.J. Ann. Rev. Crim. Proc., at iii-iv (2015) (author is a former judge on the United States Court of Appeals for the Ninth Circuit).
[11] Id. at vi-vii.
[12] Id. at iv.
[13] Timothy M. Ellmore, Fiona Rohlls & Faraz Khursheed, fMRI of working memory impairment after recovery from subarachnoid hemorrhage, 4 Frontiers in Neurology (article 179), Nov. 6, 2013, at 1, 6 fig.2.
[14] Brain Facts: A Primer on the Brain and Nervous System, Society of Neuroscience (Mar. 27, 20012), http://www.brainfacts.org/about-neuroscience/brain-facts-book.
[15] S.M Daselaar, M.S. Fleck, & R. Cabeza, Triple Dissociation in the Medial Temporal Lobes: Recollection, Familiarity, and Novelty, 96 J. Neurophysiology 1902, 1906 fig.1 (2006).
[16] Elizabeth Loftus, Our Changeable Memories: legal and practical implications, 4(5) Nature R. Neuroscience 231, 231-34 (2003).
[17] Tim Tully, et al., Targeting the Creb Pathway for Memory Enhancers, 2 Nature Reviews 267, 269 fig.1 (2003).
[18] Id. at 269.
[19] Haber & Haber, supra note 8, at 1057–58.
[20] Id. at 1058.
[21] Henry F. Fradella, Why Judges Should Admit Expert Testimony on the Unreliability of Eyewitness Testimony, 2 Fed. Cts. L. Rev. 1, 21 (2007).