Police in the United States investigate millions of crimes each year.1 Only a small percentage of the police-investigated crimes involve the use of police-arranged identification procedures. Identification procedures are unnecessary when, for example, the perpetrator is caught during the commission of the criminal act, as in the crime of driving while intoxicated, or when the victim knows the perpetrator, as in crimes of domestic violence.2
Police use identification procedures for numerous reasons. In some circumstances, the police identify a suspect during an investigation and use the identification procedure to test a witness’ ability to identify the suspect as the perpetrator. In other instances, the identification procedure is used as an investigative tool to further an investigation. A positive identification might form probable cause for a search warrant or the apprehension and subsequent questioning of a suspect, or both. Most significant for the purposes of this report are the circumstances in which a witness positively identifies the police suspect as the perpetrator, and the identification serves as compelling evidence in the prosecution of a case.
Data on the number of eyewitness identification procedures are not systematically or uniformly collected. While the exact number of eyewitness
1 Federal Bureau of Investigation, “Crime in the United States 2012: Persons Arrested,” available at: http://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2012/crime-in-the-u.s.-2012/persons-arrested/persons-arrested.
2Throughout Chapter 2, the terms law enforcement and police are used interchangeably and refer to all law enforcement agencies at the local, state, and federal levels.
identification procedures related to crimes involving strangers is unknown, mistaken identifications have disastrous effects for those wrongly accused of crimes and for society should a guilty person go free. Mistaken identifications may also erode public confidence in the criminal justice system as a whole.3 Recently, some police departments and prosecutors have implemented stringent eyewitness identification procedures in an effort to reduce erroneous convictions.4
Police-arranged eyewitness identification procedures vary greatly depending on the nature of the case. In some cases, a police-arranged identification is conducted at the very early stages of an investigation. For instance, consider the circumstance in which police respond to a bank robbery in progress. The perpetrator is described as a white male, approximately 6 feet, 2 inches in height wearing an orange shirt. As the police arrive at the crime scene, an officer observes and apprehends a man fleeing the bank wearing an orange shirt and exhibiting similar physical characteristics. In this situation, a police-arranged identification procedure may be conducted on the scene and prior to any significant investigation. At the other extreme are, for example, lengthy homicide or rape cases that include extensive investigations, forensic testing, and eyewitness interviews conducted over a protracted period of time. Such efforts may culminate in the identification of a suspect and the suspect’s inclusion in a photo array identification procedure. In such a circumstance, an eyewitness may not be asked to identify a perpetrator until months after the commission of the crime—and often after repeated probes of her or his memory by, for example, police, family members, and others.
Identification procedures may be used in different ways for different purposes. They are not always used to identify an unknown perpetrator of a crime. The police may, for example, use photo arrays and confirmatory single photographs to clarify the legal identity (birth name/government name) of an individual who is well known to a witness, but only by a street name. In such examples, a witness may know (and may have known) the perpetrator for years but may only be able to identify him by a common
3See, generally, The International Association of Chiefs of Police, “National Summit on Wrongful Convictions: Building a Systemic Approach to Prevent Wrongful Convictions,” August 2013.
4See The Innocence Project, Eyewitness Identification, available at: http://www.innocenceproject.org/fix/Eyewitness-Identification.php; U.S. Department of Justice, Office of Justice Programs, Eyewitness Evidence: A Guide for Law Enforcement (Washington, DC, 1999); Metropolitan Police—District of Columbia, General Order—Procedures for Obtaining Pretrial Eyewitness Identification, April 18, 2013; New York State District Attorneys Association Best Practice Committee, New York State Photo Identification Guidelines, October 2010; Rhode Island Police Chiefs Association, Lineup and Showup Procedures (Eyewitness Identification), November 2011; and Innocence Project of Texas, Eyewitness Identification Reform, available at: http://www.ipoftexas.org/eyewitness-id.
street name, such as “Prince.” The police typically will use an identification procedure to identify the “Prince” to which the witness is referring before they make an arrest or take other investigative measures such as the execution of a search warrant.
This chapter reviews the eyewitness identification procedures commonly used by the police and concludes with a brief discussion of situations in which citizens engage in identifying perpetrators without police assistance.
The photo array is the most common police-arranged identification procedure used in the United States.5 A photo array consists of six to nine photographs displayed to a witness. An officer might create an array by selecting photographs of persons deemed to resemble the perpetrator.6 Officers might then display the photographs one at a time to the witness and ask whether she or he recognizes each one. This method is known as a sequential procedure. Officers might also create photo arrays by cutting six square holes in a folder and taping the photographs to the back of the folder so that the faces of the fillers (non-suspects) and suspect are displayed together. When such photographs are presented simultaneously as a two by three matrix, this type of array is referred to as a “six pack.” When, as in this instance, photographs are displayed together, this is referred to as a simultaneous procedure.
In 1999, Attorney General Janet Reno released the U.S. Department of Justice, Eyewitness Evidence: A Guide for Law Enforcement,7 one of the earliest efforts to establish standardized procedures for police-arranged eyewitness identification. The guide set forth rigorous criteria and basic procedures to promote accuracy in eyewitness evidence.8 However, after the guide was released, most police departments in the United States did not adopt these procedures.
Today, many police departments use computer systems to access image databases and assemble photo arrays. Officers enter physical characteristics (e.g., race, gender, hair color) specific to the suspect into a computer, and the system retrieves filler photographs with the desired attributes. If an officer determines that a photograph in the array is suggestive or otherwise inappropriate, she or he can reject one or more fillers and instruct the system
5Police Executive Research Forum, “A National Survey of Eyewitness Identification Procedures in Law Enforcement Agencies,” March 2013, p. 48.
6Historically, the photographs were mug shots in the possession of a police department.
7U.S. Department of Justice, Office of Justice Programs, Eyewitness Evidence: A Guide for Law Enforcement (Washington, DC, 1999).
8Ibid, pp. 11–38.
to provide alternate photographs. Departments may conduct the procedure without revealing to the witness how many photographs she or he will view.
In recent decades, many police agencies and prosecutors have adopted sequential presentation of photographs, based on the belief that this approach improves the performance of an eyewitness. Currently, however, there is no consensus among law enforcement professionals as to whether the sequential presentation procedure is superior to the simultaneous procedure (see Chapter 5). The District of Columbia Metropolitan Police Department, for example, does not endorse either simultaneous or sequential procedures in its Procedures for Obtaining Pretrial Eyewitness Identification.9 The District Attorneys Association of the State of New York in 2010 adopted recommended policies for New York State and endorsed the simultaneous method.10 On the other hand, in North Carolina, legislation was passed that requires that lineup photographs be presented sequentially,11 and in Massachusetts, the Supreme Judicial Court Study Group on Eyewitness Identification recommended sequential procedures as best practice for Massachusetts Police Departments.12
The committee was presented with information regarding improvement efforts from states including New Jersey, Oregon, Rhode Island, Texas, New York, and Massachusetts. However, the committee is unable to determine the percentage of police departments that have adopted policies for eyewitness identification procedures and instituted training in these procedures.13 Some police departments require that photo arrays be presented to the witness during a procedure that is either “double blind” or “blinded.”14 (See Box 2-1 for a discussion of blinding as used in scientific practice and blinding as used in eyewitness identification procedures.) Blinding is used to prevent conscious and unconscious cues from being given to the witness. In a double-blind procedure, an individual who does not know the identity of the suspect or the suspect’s position in the photo array shows a photo array to the eyewitness. In cases where such a double-blind procedure is
9See Metropolitan Police—District of Columbia, General Order—Procedures for Obtaining Pretrial Eyewitness Identification, April 18, 2013.
10See New York State District Attorneys Association Best Practice Committee, New York State Photo Identification Guidelines, October 2010.
11N.C. Gen. Stat. § 15A-284.52 (West 2007).
12See Massachusetts Supreme Judicial Court Study Group on Eyewitness Identification, Report and Recommendations to the Justices (2013).
13The Police Executive Research Forum’s 2013 survey of eyewitness identification procedures in law enforcement agencies [Police Executive Research Forum, A National Survey of Eyewitness Identification Procedures in Law Enforcement Agencies, (2013)], notes that most agencies that completed the survey have no written policy for eyewitness identification procedures and that more agencies provide training to their employees than have written policies. See pp. 79–80.
14Police Executive Research Forum, p. 64.
not feasible, a “blinded” procedure will approximate the condition of double-blinding. For example, the photo array may be administered by an individual who knows who the suspect is, but is unable to tell when the witness is looking at the suspect’s photo and so is unable to provide even subconscious feedback to the witness. In one common “blinded” procedure, the officer places each photo in a separate envelope or folder and then shuffles the envelopes/folders so that only the witness sees the images therein. Additional recommendations to minimize the possibility of biasing feedback to the witness include requiring that the officer read instructions to the witness from a pre-printed form.15
If the witness identifies someone from the photo array, some departments ask the witness for a confidence statement. Based upon information presented to the committee, it appears that police departments do not always document identification procedures in instances when an identification is not made. Further, if a witness does make an identification, practices differ as to how such information is documented and preserved. Some agencies, for example, require officers to document this information in a written report. Others make audio or video recordings of the identification procedure.
A live lineup is a police-arranged identification procedure in which the physical suspect and fillers stand or sit in front of the witness (either individually, i.e., sequentially or en masse, i.e., simultaneously). The police generally use at least five fillers. Fillers are selected for their physical similarities to the suspect (gender, race, hair length and color, facial hair, height, skin tone, and other distinguishing features). The fillers are presumed to be unknown to the witness. Traditionally, the suspect and fillers are seated or stood in a row, and the witness views the lineup from behind a two-way mirror. Police use both simultaneous and sequential procedures for live lineups.
Live lineups are used in some jurisdictions, but they are not the predominant method used by law enforcement.16 The use of these police identification procedures is limited for a variety of reasons. First, in certain circumstances, legal counsel may be required at a lineup, thereby making it less attractive to police and prosecutors. Second, in smaller jurisdictions, it may be difficult to obtain suitable fillers (e.g., those with appropriate
15As discussed in Chapter 3, the courts have been sensitive to the potential for misidentification resulting from “suggestive” identification procedures and have set standards for admissibility of evidence.
16Police Executive Research Forum, p. 48.
Empirical evidencea has shown that the beliefs, desires, and expectations of researchers can influence, often subconsciously, how they observe and interpret the phenomena they study and thus the outcomes of experiments. This evidence has influenced how scientists carry out their experiments, resulting in the use of blind or double-blind procedures to control for this form of bias. Blind assessmentb has been used since the late 18th century; an early medical trial in 1835 used double-blind assessment, and psychologists started using blinding in the 20th century.c By the 1950s, blind assessment in randomized controlled trials was considered standard procedure in both psychological and medical research. Currently, virtually all of science uses some form of blinding.
In single-blind experiments, participants do not know which treatment they are receiving; this form of blinding is used widely across scientific fields. In experiments involving humans, as in medical or psychological research, double-blind procedures are used to guard against “expectancy effects” for both participants and researchers. In a classic double-blind clinical trial, some patients receive active medication and others are given an alternative (either a “standard treatment” or a similar-looking placebo without active ingredients), but neither researchers nor participants know who is receiving which treatment.
In an eyewitness identification setting, double-blinding can be used to prevent a lineup administrator from either intentionally or unintentionally influencing a witness. In these cases, neither the eyewitness nor the administrator knows which persons in a photo array or live lineup are the suspected culprits and which are the fillers.d,e In eyewitness identification procedures, as in science, the purpose of double-blinding is to prevent the conscious or subconscious expectations of the administrator from influencing the witness or research outcomes.
In a double-blind photo array, the officer or detective conducting the investigation reads a set of standard instructions to the witness. The instructions may include an advisory that the officer about to show the photos does not know whether any of the photos are of the person who committed the crime. The officer then leaves the room and a second officer—perhaps a patrol officer—displays the
physical similarities to the suspect). Third, conducting a lineup requires a significant amount of time and labor, 17 thereby making photo arrays a more attractive alternative that may be undertaken promptly and with less demand on department resources.
17Live lineup construction may be further constrained by the inability to hold a suspect in custody without probable cause. See Chapter 3.
photos. It is the duty of this second officer (the “blind administrator”) to show the photos and, if an identification is made, document what the witness said and ask the witness how certain she or he is of their identification. Once all photos have been shown, the officer reports the result of the procedure to the investigating officer (preferably out of earshot from the witness).
As an alternative to a double-blind array, some departments use “blinded” procedures. A blinded procedure prevents an officer from knowing when the witness is viewing a photo of the suspect, but can be conducted by the investigating officer. A common approach is the so-called “folder shuffle.” With a six-photo array, an officer uses eight manila folders. A photograph of a filler is placed in the top folder, and a photograph of the suspect and four additional fillers are placed in the next five folders. The six folders are then shuffled so that the officer does not know which folder contains the image of the suspect. Two folders with blank paper are placed on the bottom of the stack so that the witness is led to believe that there are more than six images in the array (this is referred to as back-loading, and it prevents the witness from knowing when she or he is about to view the last photograph). After reading instructions to the witness, the administering officer sits to the witness’ left and hands him or her one folder at a time and instructs him/her to open each folder and look at the enclosed photo. The cover of the folder blocks the officer from viewing the photo that the witness is viewing. When an identification occurs, the officer notes the witness’ words and reaction and asks about the witness’ confidence in his or her identification.
aR. Rosenthal, Experimenter Effects in Behavioral Research (New York: John Wiley, 1976).
bM. Stolberg, “Inventing the Randomized Double-Blind Trial: The Nürnberg Salt Test of 1835,” James Lind Library Bulletin (2006), available at: http://www.jameslindlibrary.org/illustrating/articles/inventing-the-randomized-double-blind-trial-the-nurnberg-salt.
cT. J. Kaptchuk, “Intentional ignorance: A History of Blind Assessment and Placebo Controls in Medicine,\” Bulletin of the History of Medicine 72(3): 389–433 (1998).
dP. Kilmartin, Presentation to the committee, February 6, 2014.
eK. Hamann, Presentation to the committee, December 2, 2013.
A showup is a police-arranged identification procedure in which the police show one person to a witness and ask if she or he recognizes that person. This procedure typically is used when the police locate a suspect shortly after the commission of a crime and within close proximity to the scene. Case law limits the time and distance from a crime during which such a procedure will pass legal standards. In response to such case law, police typically restrict showups to a two-hour time period after the commis-
sion of a crime. Ideally, officials take the witness to the location where the suspect has been detained and do not display the suspect in a suggestive manner (e.g., not in a police car, not handcuffed, without drawn weapons). However, as chases, fights, or disarmaments frequently precede showups, the apprehension of a suspect can raise safety issues that make it difficult to adhere to recommended procedures. Further, the nature of a showup does not lend itself to the use of a blinded procedure. A showup is designed to promptly clear innocent suspects, thereby sparing them from a prolonged period of detention as the investigation continues. Delaying the showup to locate an uninvolved officer may defeat that purpose. While some law enforcement agencies use a standard procedure with written instructions when conducting a showup, there is no indication that such procedures are used uniformly. Courts consider showups highly suggestive, and prosecutors urge the police to exercise caution when conducting them.
Police will, on occasion, display a single photograph to a witness in an effort to confirm the identity of a perpetrator. Police typically limit this method to situations in which the perpetrator is previously known to or acquainted with the witness.
Police also use field views in attempts to identify perpetrators. The method, which involves inviting a witness to view many people in a context where the perpetrator is thought likely to appear, is used when the police do not have a suspect but believe that the offender frequents a particular location. For example, police investigating a purse snatching may obtain information that the perpetrator frequents a particular recreation site during the lunch hour. A plainclothes officer or investigator might take the eyewitness to the site and walk around with him or her during the lunch hour without directing his or her attention to any specific individual.
OTHER PROCEDURES—MUG BOOKS AND YEARBOOKS
At times, police use other means to identify perpetrators. In the past, police sometimes had witnesses review mug shot books. Mug books have since been largely replaced by digitized images displayed on computer screens. Nonetheless, there are situations in which the police will have a witness review a large collection of photographs in an effort to identify a perpetrator. Witnesses who identify a perpetrator as being a student at a specific school might be asked to review a yearbook for that school in an
effort to identify the perpetrator. When using this method, police typically attempt to mask the names of the students. Similarly, if the offender is believed to be an individual from a certain profession, then the police might have the witness review photographs from the suspect’s professional society. Social media sites also serve as the catalyst for police-arranged identification procedures. If a witness knows that the perpetrator is a “friend” of Jane Doe through social media, then the police might have the witness review all friends of Jane Doe to see if she or he recognizes the individual.
All of these additional procedures (i.e., confirmatory photo, field view, mug books, yearbooks) have the potential to introduce biases of the sort that blind lineup procedures are designed to avoid.
NON-POLICE IDENTIFICATION PROCEDURES
In some cases, the victims or witnesses, or both, identify suspects without involving the police. A private citizen, organization, or corporation may conduct an investigation before, during, or even after reporting a crime to the police. The identification of suspects by entities other than law enforcement has become increasingly common as more businesses and private citizens use security cameras to identify criminal actors. High-resolution cameras coupled with high-capacity hard drives allow for real-time streaming of video with superior clarity. Such systems are relatively inexpensive and within financial reach of many home and business owners. Additionally, the proliferation of smart phones has put the ability to create a spontaneous, high-quality video record of an event into the hands of more and more people.
The rise of social media has resulted in the rise of private investigations and identifications using this resource. In one recent case, a stabbing victim drew a picture of her assailant and showed it to her husband.18 Upon viewing the picture, the husband believed that the assailant looked familiar and might be his ex-girlfriend. He obtained several photographs of the ex-girlfriend from her personal website and showed them to the victim who, after looking at those and other online images, identified the suspect at a lineup and at trial.
Many local, state, and federal law enforcement agencies have adopted policies and practices to address the issue of misidentification. However, efforts are not uniform or systemic.19 Many agencies are unfamiliar with
18New Jersey v. Chen, 27 A.3d 930 (N.J. 2011).
19See Massachusetts Supreme Judicial Court Study Group on Eyewitness Evidence, p. 2.
the science that has emerged during the past few decades of research on eyewitness identifications. Questions remain about the optimal design of photo array procedures, including the size of the array, the contents of the photographs, and their relationship to the context of the crime scene. Similar questions apply to the design of live lineups.20 Eyewitness identification is further complicated by the increasing number of situations in which victims and witnesses seek to identify the perpetrator of a crime without the aid of law enforcement. Such identifications raise new concerns about reliability and accuracy of the identification of individuals. Inconsistent and nonstandard practices might easily add noise to the eyewitness identification process, contaminate the witness, and bias the outcome of an identification procedure.
20The design of a live lineup is subject to more practical constraints than a photo array.