Evaluating Theories of Crime

What is a “Theory?” A statement of set of statements about the relationships between 2 or more events In criminology? Theories of crime Theories of how the criminal justice system operates A theory predicts what will happen, not how the world should be

How do you know a “good theory” when you see one? Akers’ 6 criteria for evaluating a theory 1. Logical Consistency 2. Scope 3. Parsimony 4. Testability 5. Fit with Empirical Evidence 6. Usefulness of Policy Implications

Logical Consistency Clearly Defined Concepts Concept = symbol/label that we apply to an abstract image Examples? Concepts must fit in a logical manner BAD LOGIC: All crime is caused by imprisonment

SCOPE (not the mouthwash) DEPENDENT variable How “general” is your explanation? Specific forms of crime/deviance? All crime? All crime, deviance, sin, and recklessness? All else being equal, “Wider is Better”

Parsimony INDEPENDENT (predictor) variables How complex is your explanation? Parsimony: Low self-control is single cause of crime Not: Crime caused by a combination of poverty, inequality, average daily temperature, intelligence, hair color, weight, daily stress… All else being equal, more parsimony is better!

Testability A valid theory can be falsified Non-falsifiable theories? Tautological arguments (crime causes crime) Vague and open-ended statements (Freud) Must be observe/measure concepts (little green men)

Is the theory correct? Survive empirical scrutiny Few theories are entirely correct or false To what degree is the theory supported? Preponderance of evidence support? Incorrect theories must be modified or discarded

Policy Implication All crime theories attempt to identify the “causes” of crime. Can the causes be reversed? Does the theory translate into practice? Example: Marxist theory of crime

Flow Chart for Evaluation NO = Useless, stop here Evaluate the Following: Scope Parsimony Policy Implications Falsifiable? Logical? Yes Empirical Evidence? YES NO: Modify/Discard

Correlation and Causation For Social Sciences (“Probabilistic”): X (the “cause”) must precede Y (the “effect”) X must be related to Y The correlation cannot be spurious

Ruling out Spuriousness Most commonly is the use of “Statistical Control” Observe/measure factors that might render relationship spurious Include these factors as “control variables” in a statistical model Problems with this?

Methods for Studying Crime Experiments Survey Research Cross-sectional Longitudinal

Experiments Experimental Control is better that statistical control “True Experiment” Random Assignment In criminology? Typically “quasi” experiments Rehabilitation based on theory Manipulate criminal justice system

Survey Research Typically cross-sectional Recent trend = longitudinal Usually high school students Recent trend = longitudinal Establish cause-effect ordering Stability of criminal offending