Once Upon A Crime Honors Terms

ABO

refers to the ABO Blood Group System, which classifies blood into four main types (A, B, AB, and O) based on the presence or absence of specific antigens on red blood cells.

Angel of Death

a healthcare worker or caregiver who intentionally harms or kills patients under their care.

Autopsy

a comprehensive post-mortem surgical and medical examination of a deceased person's body conducted to determine the exact cause, mechanism, and manner of death.

Ballistics 

the scientific analysis of firearms, ammunition, and projectile behavior to connect a specific weapon or shooter to a crime scene. [1, 2, 3]

Black widow

a woman who murders multiple intimate partners, spouses, or close associates—frequently for financial gain, life insurance payouts, or inheritance. [1, 2]

Bloodstain pattern analysis

the forensic study and interpretation of the size, shape, distribution, and location of bloodstains at a crime scene to reconstruct the events of a violent crime. [1, 2]

BOLO

a broadcast or alert sent to police officers—or sometimes the public—to watch for a specific wanted suspect, a person of interest, a missing person, or a related vehicle. [1, 2]

Brain Fingerprinting

a forensic science technique that uses electroencephalography (EEG) to measure electrical brain waves (specifically the P300 wave and P300-MERMER) and determine whether specific, crime-relevant information is stored in a person's memory

Child Abuse Response Team (CART)

a multi-disciplinary unit of law enforcement officers, social workers, medical personnel, and advocates that responds immediately to reports of severe child physical or sexual abuse. [1, 2, 3]

Circumstantial evidence

proof that does not directly show a crime happened, but instead requires a jury or judge to make a logical inference to connect a person to the event. [1, 2]

Cold case

an unsolved criminal investigation—most commonly a homicide, violent felony, or suspicious disappearance—that is no longer actively being pursued by detectives because all available investigative leads have been exhausted

Copycat crime

a criminal act that is modeled after, inspired by, or directly mimics a previous real-life or fictional crime publicized through the news or media.

Coroner

a public official—frequently elected—responsible for investigating sudden, violent, unexpected, or suspicious deaths to determine the cause (the medical reason a person died) and the manner (whether the death was natural, accidental, suicide, homicide, or undetermined)

DNA

refers to the use of deoxyribonucleic acid (DNA) analysis—commonly known as DNA profiling or DNA fingerprinting—to investigate, solve, or exonerate individuals in criminal cases

FBI

stands for the Federal Bureau of Investigation. It is the principal domestic intelligence and security service of the United States and the primary federal law enforcement agency under the U.S. Department of Justice. [1, 2]

FBI Profiling

an investigative technique that examines crime scenes, victim traits, and behavioral patterns to infer the personality, motivations, and characteristics of an unknown offender. [1, 2, 3, 4]

First-degree murder

is the unlawful, intentional killing of a human being that is willful, deliberate, and premeditated, or committed under specific legal circumstances like the felony murder rule.

Folie a deux

is a rare psychiatric syndrome—also known as a shared psychotic disorder or shared psychosis—in which delusional beliefs are transmitted from one individual to another.

Forensics

is the application of scientific knowledge, methods, and analysis to legal problems and crime-solving, while true crime is a non-fiction media genre that documents and investigates real-life criminal cases. [1, 2, 3]

Forensic Entomology

the scientific study of insects and other arthropods—such as beetles, mites, and maggots—found on or near human remains to aid legal and criminal investigations. In true crime and homicide cases, it serves as a critical investigative tool rather than just a dramatic plot device. [1, 2]

Fratricide

fratricide is the act of killing one's own brother.

GED Match

is an open-access, third-party database used by law enforcement and forensic genealogists to solve cold cases through a method called Investigative Genetic Genealogy (IGG) or Forensic Investigative Genetic Genealogy (FIGG). [1, 2, 3]

Genetic geneology

is a crime-solving method that combines single nucleotide polymorphism (SNP) DNA testing with traditional genealogical research to generate investigative leads

Geographic profiling

a criminal investigative methodology that analyzes the spatial pattern and locations of a connected series of crimes to determine the most probable area of an unknown offender’s residence or base of operations

Glasgow smile

is a violent facial wound created by cutting the corners of a victim's mouth toward the ears using a utility knife, razor blade, or broken glass. This act leaves a permanent, wide scar that mimics an exaggerated grin

Grooming

is the deliberate, preparatory process an offender uses to build trust, gain compliance, and establish secrecy with a victim (most commonly a child or vulnerable person) before or during exploitation

Gunshot Residue (GSR)

is the microscopic particulate and chemical debris expelled from a firearm when it is discharged

Homicide

is the killing of one human being by another

Hyoid bone

is a small, U-shaped or horseshoe-shaped bone located in the front of the neck between the lower jaw and the voice box (larynx). It is the only free-floating bone in the human body, meaning it does not connect directly to any other bone. Instead, it is held in place by muscles and ligaments and acts as an anchor for the tongue and pharynx. [1, 2, 3]

Infanticide

the intentional killing of an infant or young child, usually committed by a parent

Involuntary manslaughter

is the unlawful, unintentional killing of a human being that occurs without malice aforethought, typically resulting from criminal negligence, recklessness, or the commission of an unlawful non-felony or low-level misdemeanor.

John/Jane Doe

is a generic placeholder name used when a person's true identity is unknown, unverified, or legally concealed.

Latent print

is an invisible or hidden impression left on a surface by the friction ridge skin of fingers, palms, or soles

Locard’s Exchange Principle

states that whenever two objects or people come into contact, a mutual transfer of physical material occurs. It is often summarized by the phrase "every contact leaves a trace."

Luminol

is a chemical reagent used in crime scene investigations to detect trace, invisible, diluted, or cleaned-up blood.

MacDonald Triad

(also known as the homicidal triad or triad of sociopathy) is a set of three childhood and adolescent behaviors proposed in 1963 by American psychiatrist J.M. Macdonald as early indicators of future violent or serial criminal tendencies.

Manslaughter

is the unlawful killing of a human being without malice aforethought or premeditation. In true crime and criminal law, it carries less moral blame and a lighter prison sentence than murder

Mask of sanity

refers to an individual's outward presentation of being normal, charming, and well-adjusted while harboring a profound internal lack of empathy, conscience, or emotional depth

Matricide

is the act of killing one's own mother

Medical Examiner

is an appointed public official—typically a licensed physician and forensic pathologist—responsible for investigating sudden, unexpected, violent, suspicious, or unattended deaths

Modus operandi

refers to the specific, practical methods, techniques, and behavioral patterns an offender uses to commit a crime, avoid detection, and escape

Mr. Big

is a controversial undercover police technique—originating in Canada and occasionally used in Australia—designed to elicit confessions from suspects in cold cases, usually murders, where there is not enough direct evidence to bring charges. [1, 2, 3]

How It Works

• Fictional Gang: Undercover police officers create a fake criminal organization and befriend the suspect through staged, chance encounters.

• Escalation & Rewards: The suspect is drawn into lucrative, minor criminal tasks (such as credit card scams or debt collection) and receives financial and social benefits.

• The Meeting with "Mr. Big": After building a deep sense of loyalty, fear, or dependence, the suspect is brought before an operative playing the boss ("Mr. Big").

• The Confession Demand: The boss tells the suspect that the gang can help make their legal problems disappear—or that they cannot be trusted with a high-level job—unless they confess to their past crime

mtDNA

stands for mitochondrial DNA. It is genetic material found inside the mitochondria (the energy-producing structures) of a cell, rather than the nucleus.

Munchausen Syndrome by proxy

now officially known in medicine as Factitious Disorder Imposed on Another (FDIA)—is a rare and severe form of child abuse where a caregiver fabricates, exaggerates, or induces illness in a person under their care (usually a child) to gain attention, sympathy, or control.

Paraphilia

refers to a persistent, intense, and atypical sexual interest, fantasy, urge, or behavior

Patricide

is the act of a person killing their own father (or a father figure, such as a stepfather or adoptive father).

Petechial hemorrhaging

refers to the appearance of tiny, pinpoint red or purple spots (usually 0.1 to 2 mm in size) that form when minuscule blood vessels (capillaries) rupture and bleed under the skin or mucous membranes. They are most commonly looked for in the eyes (conjunctiva), inner eyelids, and face of a victim

Phenotyping

is the process of predicting a person's physical appearance, ancestry, and age directly from biological evidence (such as blood, hair, or skin cells) left at a crime scene.

Piquerism

is a paraphilia and a form of sexual sadism in which a person gets sexual arousal or gratification from cutting, piercing, or stabbing someone's skin with sharp objects such as pins, knives, or razors

Polygraph

is an investigative tool that measures and records involuntary physiological responses—such as blood pressure, pulse, respiration rate, and skin conductivity (sweat)—while a person answers a series of questions

Private investigator

often called a private detective—is a licensed professional hired by private citizens, businesses, attorneys, or organizations to gather factual evidence and conduct independent investigations into legal, financial, or personal matters.

Probable cause

is the legal standard under the Fourth Amendment of the U.S. Constitution that police must satisfy to make an arrest, conduct a search, or obtain a search or arrest warrant

Psychopath

is an individual with a personality construct marked by a profound lack of empathy, shallow emotions, superficial charm, pathological lying, and persistent antisocial behavior

Rape kit/SANE

• Rape Kit (Sexual Assault Evidence Kit / SAEK): A package of tools, forms, and containers used by medical professionals during a sexual assault forensic exam to collect and preserve physical and biological evidence (such as DNA swabs, blood, urine, hair, fibers, and fingernail scrapings) from a survivor. [1, 2, 3]

• SANE (Sexual Assault Nurse Examiner): A registered nurse who has received specialized clinical and forensic training to conduct comprehensive medical-legal examinations, collect evidence safely, document injuries, and provide trauma-informed care to sexual assault survivors

Rigor mortis

is the temporary postmortem stiffening of body muscles caused by chemical changes—specifically the depletion of adenosine triphosphate (ATP) and permanent cross-linking of actin and myosin filaments.

Scotland Yard

refers to the headquarters of the London Metropolitan Police Service (or the detective division within it), which has become a famous name and cultural symbol in true crime history

Second-degree murder

is the unlawful killing of a human being committed with malice aforethought, but without prior planning or premeditation. It sits between first-degree murder (which requires planning and deliberation) and manslaughter (which lacks malice)

SNP profile

(Single Nucleotide Polymorphism profile, often pronounced "snip") is a advanced DNA map used to identify suspects or unidentified human remains by building a family tree from distant genetic relatives

Sociopath

is an informal term for a person who displays traits of Antisocial Personality Disorder (ASPD), marked by a chronic disregard for the rights, safety, and feelings of others

SODDI

The SODDI defense is a legal strategy where a criminal defendant claims that someone else is responsible for the crime rather than themselves. Instead of proving a direct alibi, the defense attempts to create reasonable doubt by pointing to an unidentified individual, a vague third party, or an alternate suspect. [1, 2]

Strangulation

is the compression of the neck—using hands, arms, a ligature, or another object—that blocks blood flow or air to the brain. It causes a lack of oxygen (hypoxia) leading to unconsciousness or death.

Suffocation

suffocation is defined as the intentional, knowing, or reckless obstruction of air from reaching the lungs by blocking a person’s nose or mouth, or by restricting their chest movement. In true crime and criminology, it is categorized under mechanical asphyxia. It is legally and forensically distinct from strangulation. [1, 2, 3]

Suicide

refers to the intentional self-inflicted ending of one's own life

Touch DNA

(also called trace DNA, contact DNA, or transfer DNA) is a forensic method that analyzes microscopic amounts of genetic material left behind when a person touches an object or another person. [1, 2, 3]

Toxicology

refers to forensic toxicology—the scientific analysis of biological samples (such as blood, urine, hair, and tissue) to detect, identify, and measure drugs, alcohol, poisons, or heavy metals in criminal and medico-legal investigations

Trophy/souvenir

Trophy

• Definition: An item taken by the killer to serve as a symbol of mastery, skill, and control over the victim.

• Intent: It represents a physical "conquest". The offender uses it to remind themselves of their dominance and power.

• Nature: It is often an inanimate object of personal significance to the crime or a body part. It is tied to the ego and the psychological triumph over the victim. [1]

Souvenir

• Definition: An item taken to re-experience the memory or the sexual/emotional excitement of the crime.

• Intent: It serves as a memento to help the offender slip back into a reverie state—reliving the sexual fantasies, assault, and murder sequence long after it is over.

• Nature: It is often fetishistic. Common examples include personal belongings of the victim such as ID cards, photographs, jewelry, or female lingerie. [1]

Tunnel vision

is the single-minded focus on a single suspect or case theory, while selectively filtering, ignoring, or discounting contradictory and exculpatory evidence

Victimology

is the scientific study of crime victims, the physical, emotional, and financial harm they suffer, and their relationship with offenders and the criminal justice system

The Vidocq Society

is a real-life, exclusive, Philadelphia-based non-profit organization of forensic experts, criminologists, pathologists, profilers, and law enforcement veterans who volunteer their time pro bono to help solve unsolved homicide cold cases.

Voir dire

refers to the preliminary examination and questioning of potential jurors by the judge and attorneys to ensure a fair and impartial jury before a trial begins. [1, 2]

Y-DNA test

(specifically using Y-STR or Y-chromosome short tandem repeat analysis) in true crime and forensics is a genetic test that examines the Y chromosome—which is passed down from father to son virtually unchanged across generations