Welcome to NIJ’s Term of the Month. Each month we are featuring a term from our scientific research portfolios informing significant American justice system issues and solutions.
June 2022 - Microbial Forensics
Microbial forensics is the investigation of the cloud of biological evidence humans leave behind at crime scenes that includes bacteria, fungi, viruses, and other microbial evidence. Researchers have learned over the past 20 years that each person carries a distinct microbial signature that is shed into the environment and left on objects that are touched. The number of microbes in the biological clouds that surround each of us is enormous, but because they are invisible to the eye, we are unaware of them.
The microbial communities living in association with the human body make up an individual’s microbiome, and the bacteria alone are typically 10 times more prevalent on a body than human cells. About 3% of a person’s body mass is made up of microbes.
The birth of microbial forensics came with the 2001 attacks in Washington, D.C. using anthrax spores. The efforts to identify the strain of anthrax established microbial forensics as an investigative tool, and since that time it has been used to detect microbial traces on phones, doorknobs, keyboards, and other objects a suspect may have touched. In the future a microbial signature may reveal details about a person’s diet, health, and drug use.
The Search for a Microbial Death Clock (article)
The Evidence We Leave Behind: Part 1 (podcast)
The Evidence We Leave Behind: Part 2 (podcast) available on June 6 from NIJ’s podcast page.
Unmanned aircraft systems is a term that encompasses not only the unmanned aircraft vehicle but also the flight controller on the ground, and the system of communication between the two. Under FAA Part 107, unmanned aircraft vehicles are air vehicles weighing between a half and 55 pounds that operate by remote pilot and are often fitted with specialized cameras, GPS, and/or other sensors that collect and often relay information via a communications link to a variety of destinations, including the remote pilot and/or a command center. In law enforcement, unmanned aircraft systems are used in a variety of ways, including crowd control, traffic and accident reporting, search and rescue, crime scene reconstruction, pre-operational situational awareness to optimize officer and individual safety (e.g. by gathering information for bomb threats and hostage situations), and even as first responders.
Unmanned aircraft systems are subject to the rules set forth by the Federal Aviation Administration to maintain safe national airspace, specifically Unmanned Aircraft Rules (Part 107). Since unmanned aircraft systems also are operated from a remote command and control center and relay information, equipment must be certified by the Federal Communications Commission to minimize harmful radio interference. Most unmanned aircraft system pilots are required to maintain visual-line-of-sight (VLOS) with their aircrafts, with the exception of those who have beyond-visual-line-of-sight (BVLOS) certification.
Community corrections is a term for managing individuals convicted of a crime and serving their sentences in a community setting, rather than in prison or jail. Community supervision is another term for community corrections. Probation and parole are two primary forms of community corrections. Community supervision may also be ordered for individuals awaiting trial.
Probation is an alternative to jail, or sometimes prison, ordered when the sentencing court decides that the crime does not warrant incarceration. Probation officers supervise individuals on probation, monitoring their activities and ensuring compliance with conditions of supervision. Conditions of supervision include avoidance of crime and association with individuals with felony sentences and may include school attendance, employment, testing for drugs or alcohol, or other milestones to be met by the sentenced individual.
Parole is supervised release from prison after a portion of a sentence has been served. Parole is granted when a parole board or other authorized public body determines that release of an individual from confinement is justified in light of evidence of rehabilitation and public safety interests. Persons on parole, like those on probation, regularly meet with supervision officers and satisfy conditions of parole to complete their sentence.
The philosophy underlying community corrections is to prevent criminal behavior through close supervision and the imposition of restrictions on probation or parole in an environment designed to be more conducive to rehabilitation while maintaining public safety. A related goal of community corrections is the reduction of overcrowding of prisons and jails.
Community Corrections, NIJ.gov Topic page with article listings.
“Tapping into Artificial Intelligence: Advanced Technology to Prevent Crime and Support Reentry,” by Eric Martin and Angela Moore, NIJ.gov, August 6, 2020. NIJ.gov. This article originally appeared in the June/July 2020 issue of Corrections Today, as submitted by the National Institute of Justice. It was reprinted with permission of the American Correctional Association.
“The Role of Human Service Providers During Community Supervision,” by Cecelia Klingele, National Institute of Justice, NIJ.gov, September 2021.
“Crime and Desistance: Probing How Probationers' Thoughts on Crime May Inform Their Conduct,” July 20, 2021, NIJ.gov article based upon the research report “Research on Offender Decision-Making and Desistance From Crime: A Multi-Theory Assessment of Offender Cognition Change.” Principal Investigator: Caleb D. Lloyd. The research was funded by NIJ award 2014-R2-CX-0009, awarded to The University of Texas at El Paso.
“The NIJ Recidivism Forecasting Challenge: Contextualizing the Results,” by Veronica White, D. Michael Applegarth, Joel Hunt, and Caleb Hudgins, National Institute of Justice, February 2022.
Situational crime prevention (SCP) is a crime reduction strategy used by law enforcement that stemmed from the analysis of circumstances that give rise to particular types of crime. SCP posits that criminal acts may be deterred by strategic environmental or managerial changes. It differs from other crime prevention strategies because it focuses on the setting for crime, rather than those committing criminal acts. The main goal of situational crime prevention is to make criminal acts less attractive to people who might potentially offend.
There are a multitude of ways this can be accomplished, including increasing the risk and reducing the reward of committing a crime, removing the target, increasing surveillance, controlling weapons, and alerting the offending person’s conscience. As such, it requires assistance from the leadership at a number of public and private locations that tend to attract crime, including schools, hospitals, parks, bars, stores, and transit.
- Understanding the Causes of School Violence Using Open Source Data
- Evaluation of a Situational Crime Prevention Approach in Three Jails: The Jail Sexual Assault Prevention Project
- Understanding the Causes of School Violence Using Open Source Data
- Situational Approaches to Making Communities and Correction Institutions Safer
There also are promising practices related to situational crime prevention on CrimeSolutions:
- Closed Circuit Television (CCTV) Surveillance
- Improved Street Lighting
- Metal Detectors and Security Screenings at Airports as a Counterterrorism Strategy
- Alley Gating in the United Kingdom
NIJ continues to fund research with the goals of understanding the effects and usefulness of situational crime prevention. Ongoing research projects include:
A major theory in socio-behavioral and other sciences, life course theory posits that individual life experience is connected to dynamics that are driven by historical and socioeconomical factors.
In the criminological context, the central idea of life course theory is that childhood antisocial behavior, adolescent delinquency, and early adult criminal infractions are more likely when an individual's bond to society is weak or broken. It stresses turning points that may occur over an individual’s life course which affect their connection to society and its institutions, levels of social control, and thus likelihood to become involved in criminal behavior.
The theory is an effort to offer a comprehensive outlook on the study of criminal activity by considering a multitude of factors that affect offending across different time periods and contexts. The goal is to explain the onset of, persistence of, and desistance from offending behavior over the life course of an individual.
The Trafficking Victims Protection Act (TVPA) of 2000 was the first Federal law to address the trafficking of persons, aimed at the prevention, protection, and prosecution of both labor trafficking and sex trafficking. The TVPA created the most widely accepted definition of labor trafficking: "the recruitment, harboring, transportation, provision, or obtaining of a person for labor or services, through the use of force, fraud, or coercion for the purpose of subjection to involuntary servitude, peonage, debt bondage, or slavery” (DHS Human Trafficking Laws & Regulations).
Per the National Action Plan to Combat Human Trafficking, “Labor trafficking occurs across many different industries, including domestic work, traveling sales crews, food services, peddling and begging, agriculture, health and beauty services, construction, hospitality, and landscaping.”
- Article: How Does Labor Trafficking Occur in U.S. Communities and What Becomes of the Victims?
- Article: The Prevalence of Labor Trafficking in the United States
- Podcast: Human and Labor Trafficking in the U.S.
- Data-collection: Human Trafficking Reporting System
- Report: Prosecuting Human Trafficking Cases: Lessons Learned and Promising Practices
- Report: Understanding the Organization, Operation and Victimization of Labor Trafficking in the United States
- Report: An Exploratory Study of Labor Trafficking Among U.S. Citizen Victims
NIJ continues to fund research with the goals of understanding and preventing labor trafficking. Select ongoing research projects:
- Understanding the Trafficking of Children for the Purpose of Labor in the United States
- Evaluating the OHTS Tool and Assessing Outcomes for Human Trafficking Survivors
- Labor trafficking in construction and hospitality: Analyzing victim recruitment, exploitation, and service needs to identify strategies for prevention and intervention
- Understanding What Works in the Successful Identification, Investigation, and Prosecution of Labor Trafficking Cases in the United States
Machine learning is the study of computer algorithms that improve automatically through experience. It refers to the development of systems that can learn from data. A machine learning algorithm can, after exposure to an initial set of data, evaluate new, previously unseen examples and relate them to the initial “training” data. It is ideally suited for classification problems that involve implicit patterns, and it is most effective when used in conjunction with large amounts of data.
Criminal justice applications of machine learning include detecting patterns and anomalous behavior, predicting crowd behavior and crime patterns, protecting critical infrastructure, and uncovering criminal networks.
Read an NIJ Journal article on the role of machine learning in criminal justice.
Desistance is generally understood to mean the reduction in criminal behavior over time. It is the process of individuals ceasing engagement in criminal activities. Varying definitions and measurement strategies have evolved over the years. Early scholarship tended to view desistance as a discrete event — that is, the termination of offending or end of a criminal career. More recent definitions, however, suggest that desistance is instead a developmental process by which criminality declines over time.
In NIJ’s new publication Desistance From Crime: Implications for Research, Policy, and Practice, Dr. Michael Rocque offers an updated, theoretically grounded definition as a foundation for future work: Desistance is “the process by which criminality, or the individual risk for antisocial conduct, declines over the life-course, generally after adolescence.”
Related NIJ resources:
NIJ hosted a webinar during which the authors presented and discussed key themes from each of their chapters. Watch a recording of the webinar.
Historically called domestic violence, intimate partner violence describes physical, sexual, or psychological harm by a current or former intimate partner or spouse. Types of intimate partner violence include physical violence, sexual violence, threats of physical or sexual violence, psychological/emotional violence, and stalking.
Violence by an intimate partner is linked to both immediate and long-term health, social, and economic consequences. Factors at all levels — individual, relationship, community, and societal — contribute to intimate partner violence. This type of violence can occur among heterosexual or same-sex couples.
Preventing intimate partner violence requires reaching a clear understanding of those factors, coordinating resources, and fostering and initiating change in individuals, families, and society.
Related NIJ resources:
New Approaches to Policing High-Risk Intimate Partner Victims and Offenders (NIJ Journal Issue 282)
Employing Research To Understand Violence Against Women (NIJ Journal Issue 281)
Dual system youth are a subset of “crossover youth” — juveniles who have been victims of maltreatment and have also engaged in delinquent acts. The dual system youth population consists of crossover youth who have entered, at some point, both the child welfare and juvenile justice systems. This vulnerable and high-risk group has unique, complex needs that demand a collaborative approach by the child welfare and juvenile justice systems.
The Dual System Youth Design Study, led by investigators at California State University Los Angeles and supported by NIJ and the Office of Juvenile Justice and Delinquency Prevention, suggests that more than half of the juvenile justice population has or will have child welfare involvement.
Related NIJ content:
In forensic science, an alternate light source uses monochromatic light to detect and identify physical evidence, including bruises, body fluids, hair, clothing fibers, and other trace materials. This technology takes advantage of a material’s inherent luminescent properties that cause it to glow when struck with a specific wavelength of light.
Related NIJ content:
Novel psychoactive substances (NPS), also referred to as designer drugs and synthetic drugs, are an emerging or re-emerging type of illicit substance. NPS are similar in structure and effect to common drugs of abuse, but differ enough that they evade detection with traditional tests and require new scheduling laws. NPS pose serious complications for both consumers and forensic scientists because their use may be linked to severe health problems and their chemical modifications makes them difficult to identify.
Read about research on NPS in the NIJ Journal article, Identifying New Illicit Drugs and Sounding the Alarm in Real Time, and in an article written by NIJ scientist Frances Scott, NPS Discovery and the Hunt for New Drugs of Abuse.
Mass spectrometry is a tool for measuring different fragments of a compound. In forensic science, mass spectrometry can be used, for example, to identify and discriminate individual drugs in seized substances. A mass spectrometer takes a sample, ionizes and breaks the compounds in it, and sorts the fragments by the ratio of their weight to their charge. The pattern of the captured fragments makes a spectral signature that can be used to identify the compound.
Resources and information
- Fast and Portable Drug Testing: Dual-Method Prototype Shows Promise for Court-Admissible Drug Testing
- Carbon-Based Fingerprint Powder as a One-Step Development and Matrix Application for High-Resolution Mass Spectrometry Imaging of Latent Fingerprints
- NIJ-funded research involving mass spectrometry
- Publications from NIJ-funded research involving mass spectrometry
NamUs is a national repository and resource center of information related to missing, unidentified, and unclaimed person cases. Funded and administered by the National Institute of Justice, NamUs fills the nation’s need for a central, online, secure database of unidentified remains and missing persons records. The database is searchable by all, with biometric and other secure case information accessible only to appropriate, vetted criminal justice users. All NamUs resources are provided at no cost to law enforcement, medical examiners, coroners, allied forensic professionals, and family members of the missing.
Resources and information --
- Justice Department Fights for the Missing
- Justice Department Partnership Finds More than 300 Unidentified Persons Through Fingerprint Analysis
- Serial Killer Connections Through Cold Cases
- Searching for the Missing in a City of Millions
- Lost But Not Forgotten: Finding the Nation's Missing
Reintegration is when an individual transitions from being incarcerated in a prison or jail to living in a community and attempting to maintain a crime-free lifestyle.
Technology-facilitated abuse refers to harmful acts or courses of conduct facilitated through digital means that can compromise victims’ privacy and cause them to fear for their safety. Examples of such conduct are cyberstalking, nonconsensual pornography, swatting, doxing, and sextortion.
Personal harm from digital abuse extends far beyond the digital realm. These acts can cause serious psychological distress and damage relationships with family, friends, and partners and disrupt educational and professional pursuits.
Sextortion — A form of cyber extortion featuring an online attack on victim systems, for example through ransomware, in which offenders demand sexual images, sexual favors, or other things of value in exchange for stopping the attack.
Nonconsensual pornography — Distribution of nude or sexually explicit images or videos of an individual without consent.
Cyberstalking — Repeated use of electronic communications to stalk a person or group.
Doxing — Public release of private and sensitive personal identifying information about an individual without their consent. (The word “doxing” is derived from “documents.”)
Swatting — False report of an emergency to trigger an emergency response, specifically deployment of a SWAT team, to a location where no emergency exists.
Pediatric bruising patterns are tell-tale bruising patterns in injured children in order to differentiate between accidental injuries and physical abuse. Bruising on a child’s ear, buttocks, feet, or hands, for example, are not typical of accidental injuries and should alert physicians to possible abuse.
- Child Abuse or Accident? Bringing Science to Pediatric Emergency Departments and Forensic Investigations
- Impact Sites Representing Potential Bruising Locations Associated With Rearward Falls in Children
- Development of a Surrogate Bruising Detection System to Describe Bruising Patterns Associated with Common Childhood Falls
- Bruising as a Forensic Marker of Physical Elder Abuse
Using data, analysis, and research to complement experience and professional judgment, in order to provide the best possible police service to the public.
Evidence-Based Policing refers to scientific evidence, not evidence in the legal or investigative sense.
[note 1] Sampson, R.J. & J.H. Laub. (1993). Crime in the Making: Pathways and Turning Points Through Life. Boston: Harvard University Press.