The justice system employs two main approaches to gauging risk, both with long histories in American justice practice. Criminal justice decision-makers with specialized knowledge and experience can make individual determinations based on that knowledge and experience. This is the professional or clinical judgment approach. Alternatively, risk can be measured through tools that synthesize a number of factors, such as criminal history, related to future criminal offending or misconduct, through statistical analysis of outcomes for similar individuals. This is the actuarial risk assessment approach.
Though risk continues to be gauged in both ways, criminal justice experts and practitioners agree that the actuarial approach is integral to evidence-based practice. This is because:
- Actuarial assessment outperforms clinical judgment alone in predicting outcomes
- Actuarial assessment supports consistency in criminal justice decision-making
- Applying criminal justice interventions (such as treatment) by actuarially-determined level of risk is necessary in order for those interventions to be effective
This quantitative, tool-based method of risk prediction is called “actuarial” because it is based on examining data on populations to see what characteristics are predictive of the relevant outcome — just like insurance actuaries use data to set auto insurance premiums. By examining data on all of their policyholders, insurance companies have determined that factors such as age and past driving record are strongly predictive of an individual’s likelihood of being in a car accident. Risk in this sense is a probability: the likelihood of a bad outcome over a period of time, based on past outcomes for a similar group of individuals.
It is important to emphasize that measuring risk tells how likely a bad outcome is to occur. It does not say with certainty that someone will or won’t reoffend. Labeling someone as “high-risk” to reoffend does not mean that individual will definitely reoffend; rather, it means that a large number of people sharing these characteristics have reoffended in the past. The insurance company can’t know which people will be in car accidents, but it can know what combination of attributes make the odds of an accident a lot higher.
Risk is also distinct from stakes, or how serious or harmful the nature of the reoffending will be. The risk discussed in the justice system often refers to any kind of offending. Certain kinds of offenses are higher stakes, particularly violent and sexual crimes, because they are uniquely damaging. It is possible to predict risk for high-stakes offending specifically, and it is important to understand that high risk does not necessarily mean at high-risk to engage in violent victimization.
Risk and Need
In many justice contexts, risk is discussed in conjunction with needs. Needs commonly refer to changeable criminogenic factors that are related to the likelihood of reoffending, such as substance dependence. The conceptual difference between risk and need is muddy, and the fact that they are sometimes used interchangeably only adds to the confusion.
In general, the distinction between risk and needs has more to do with the role they play in justice processes than with measuring different concepts. As discussed above, risk is the likelihood of re-offense, and it tells the justice system who to focus on, whether for detention or release, level of supervision, or intervention. Need factors provide targets for programming and services intended to change behavior and thereby reduce risk. They can also be used to predict risk along with other risk factors, but their use in risk assessment (i.e., prediction) is not the same as their role in needs assessment (i.e., problem identification). This distinction of different roles of needs is often overlooked, leading to miscommunication about what they are and how they should be used.