Notes on The Dismal Science: The Irrational 18-Year-Old Criminal
Introduction to Crime Control
Crime control is a longstanding issue in social science, traceable to the work of Cesare Beccaria, an 18th-century philosopher.
The primary tools for controlling crime include policing and imprisonment.
Deterrence Theory
Deterrence aims to prevent crime by discouraging potential offenders through the fear of punishment.
Two mechanisms of deterrence:
Perception of being caught (policing)
Fear of imprisonment (punishment)
Deterrence encourages constructive activities over criminal ones.
Challenges of Measuring Deterrence
Empirical measurement of deterrence is complex:
Tougher policies (longer sentences, more policing) are often responses to rising crime, not proactive measures.
This complicates the analysis as the relationship between crime rates and deterrent policies is bidirectional.
Innovative Research Methods
Economists David S. Lee and Justin McCrary conducted a study in Florida to analyze the effect of turning 18 (which incurs stiffer penalties).
They utilized a dataset of felony arrests in Florida (1989-2002), including birth dates to track criminal behavior pre- and post-18th birthday.
Findings on Arrest Rates
Probability of being sentenced to prison for an offense increased from 3% to 17% at age 18.
Key finding: No significant decrease in crime rates as offenders approach 18 despite increased prison sentence probabilities.
Suggests deterrence via fear of punishment does not work effectively for this age group.
Incapacitation versus Deterrence
Ineffectiveness of Deterrence: No significant drop in arrest rates correlating with heightened legal penalties.
Incapacitation Effect: Prison does prevent crime by caging individuals:
20% of those arrested a week before 18 were re-arrested within a month.
Only 10% of those arrested a week after 18 were re-arrested in the same timeframe, as they spent more time incarcerated.
Implications for Policing
Questions arise regarding the efficacy of increased policing:
Lack of causal evidence linking police numbers to crime rates.
Prior work suggests that current data does not provide clarity on this relationship.
Conclusion
Recent studies challenge traditional beliefs about the effectiveness of deterrence in crime control.
This ongoing debate is important in shaping future policies and understanding the dynamics of crime and punishment.