Definition
A lineup is a police identification procedure in which a witness or victim views a group of individuals—typically five to eight people—to determine whether they can identify the perpetrator of a crime. Lineups serve to test witness recognition while minimizing suggestive influences that might lead to false identifications. The suspect appears alongside "fillers"—individuals who match the general description but are known to be innocent—ensuring the witness must make a genuine identification rather than simply picking whoever looks most suspicious. Proper lineup procedures require that all participants share similar physical characteristics (height, build, race, age), that the lineup administrator doesn't know which person is the suspect (double-blind procedure), and that witnesses are instructed the perpetrator may not be present. Lineups can be conducted live, with individuals standing in a room, or through photo arrays showing pictures of potential suspects. The reliability of lineup identifications has been questioned by research showing that witness memory is fallible and that suggestive procedures can lead to false identifications, prompting reforms in how lineups are conducted and evaluated.
Historical Context
Lineups emerged as a formal police procedure in the late 19th and early 20th centuries as departments sought systematic methods for witness identification. Early lineups were often conducted informally, with suspects presented alone or in groups that made them stand out, leading to unreliable identifications. By the 1940s noir era, lineups had become standard procedure in major police departments, typically conducted in dedicated rooms with one-way mirrors allowing witnesses to view suspects without being seen. The noir-era lineup often involved dramatic confrontations, with witnesses pointing through glass at suspects who stood under harsh lights. Procedures were less rigorous than modern standards—lineups might include only three or four people, fillers might not match the suspect's description, and administrators often knew which person was the suspect, potentially influencing witnesses through subtle cues. The period's lineups reflected broader attitudes about criminal justice: confidence in eyewitness memory, less concern about false identifications, and acceptance of procedures that would later be recognized as suggestive and unreliable.
In Detective Work
Modern lineup procedures follow strict protocols designed to maximize reliability and minimize false identifications. Investigators select fillers who match the witness's description of the perpetrator, not the suspect's actual appearance, ensuring the lineup tests recognition rather than simply asking witnesses to pick whoever looks most like a criminal. Double-blind administration—where the lineup administrator doesn't know which person is the suspect—prevents unconscious cues that might influence witnesses. Witnesses receive instructions emphasizing that the perpetrator may not be present and that they should not feel pressured to make an identification. Sequential lineups, where witnesses view individuals one at a time rather than simultaneously, reduce the tendency to make relative judgments (picking whoever looks most like the perpetrator) rather than absolute judgments (recognizing the actual perpetrator). Investigators document the entire procedure, recording witness statements about their certainty and any comments made during viewing. Despite these improvements, lineup identifications remain controversial, with research showing that even well-conducted lineups can produce false identifications, particularly when witnesses are uncertain or significant time has passed since the crime.
In Noir Fiction
Noir fiction treats lineups as dramatic moments of truth where justice hangs on a witness's ability to recognize a face glimpsed in darkness or trauma. The classic noir lineup scene shows a nervous witness staring through one-way glass at a row of men under harsh lights, the detective asking "Is he there? Take your time." Films like "The Naked City" and "Detective Story" feature lineups as pivotal scenes where cases are made or broken. Yet noir also explores the darker side: the witness who identifies the wrong person out of fear or pressure, the corrupt cop who stacks the lineup to ensure identification, the innocent man who looks guilty simply because he's the only one matching the vague description. Noir recognizes that lineups test not just recognition but memory, confidence, and the power of suggestion. The femme fatale might deliberately misidentify to protect her lover, the frightened witness might pick someone just to end the ordeal, and the hardboiled detective must determine whether the identification represents genuine recognition or the witness telling police what they want to hear.
In OnlinePuzzle
The term "LINEUP" appears across OnlinePuzzle's game modes as a police procedure vocabulary word. In Daily 5, players might deduce it from clues about identification procedures or witness recognition. Scramble presents "LINEUP" as a 6-letter word requiring quick pattern recognition. Word Search grids hide it among other police procedure terms like "WITNESS" and "IDENTIFICATION," while Memory Clues might pair lineup concepts with related imagery—a one-way mirror, silhouettes standing in a row, a witness pointing. The word reinforces the game's authentic police procedural atmosphere, connecting players to the identification methods that real investigators use to link suspects to crimes.
Examples in Context
Robbery Investigation: A convenience store clerk who witnessed an armed robbery views a six-person photo lineup. She immediately identifies suspect number four with high confidence, stating "That's definitely him—I'll never forget those eyes." The identification, combined with other evidence, leads to the suspect's arrest and eventual conviction. The clerk's certainty and the proper lineup procedure make the identification reliable evidence.
Wrongful Identification: A witness to a nighttime assault views a lineup and tentatively identifies a suspect after initially saying none of the individuals looked familiar. Years later, DNA evidence exonerates the convicted man, revealing that the witness's uncertain identification—influenced by suggestive police procedures—led to a wrongful conviction. The case demonstrates the dangers of unreliable lineup procedures.
OnlinePuzzle Gameplay: In a Daily 5 puzzle, the clue reads "Police identification procedure (6 letters)." Players must work through the law enforcement context and letter patterns to arrive at "LINEUP," connecting the abstract clue to the concrete procedure that tests witness recognition in the noir detective world.
Related Terms
- Witness - The person who views the lineup
- Identification - The process lineups facilitate
- Eyewitness - Someone who directly observed the crime
- Photo Array - Lineup using photographs instead of live people
- One-Way Mirror - Glass allowing witnesses to view unseen
- False Identification - Incorrect lineup identification