Estimating Size of Drug Users in Macau: an Open Population Capture-Recapture Model with Data Augmentation Using Public Registration Data

Successful drug intervention policies rely on timely assessment of size of drug users and close monitoring of trend regarding drug abuse. Taking advantage of data collected by the Central Registration System for Drug Abusers of Macau (CRSDAM), this study applied open population capture-recapture models with data augmentation techniques to estimate the size of drug users and to identify influential factors on capture and survival probabilities from 2009 to 2014. In particular, the data augmentation technique was used to address missing data issues. The estimated size of drug users has been slowly declining from 2442 (95% Bayesian credible interval [BCI] 2042–2914) in 2009 to 807 (95% BCI 654–1000) in 2014 with a small fluctuation of 2251 (95% BIC 1950–2599) in 2011, and the estimated cumulative size of drug users is 6199 (95% BCI 5651–6873), which is correspondent to a prevalence rate of 1.20% of the current population aged 15 to 54. Although the estimated sizes of total, narcotic, and other drug users were declining, the size of stimulant users might be increasing. People who used narcotics as their first drug and who were reported by governmental agencies were more likely to stay in the registration system, while those who used needle injection were less likely to stay. Governmental agencies, higher education, and using needle injection were negatively associated with the probability of capture over time, while using narcotics as the first drug was positively associated with it.     

Strengthening cross-border law enforcement cooperation in the EU: the Prüm network of data exchange

The Prüm network was established to provide mechanisms and the infrastructure to achieve a closer cooperation between the EU member states in combating terrorism, organised crime and illegal immigration through the cross border exchange of DNA profiles, fingerprints and vehicle registration data. While Prüm offers clear benefits for cross-border policing, it continues to present challenges of a technical and scientific nature as well as legal, ethical and socioeconomic concerns. This article reviews these challenges as well as the existing safeguards. It argues that, in order to achieve Prüm benefits and maximise its potential, it is important to enhance the necessary dialogue and cooperation between member states so as to confront the above concerns and address challenges posed by Prüm through balanced measures.     

Unemployment and crime: the role of apprehension

An increase in the unemployment rate decreases the opportunity cost of crime and increases the crime rate according to standard microeconomics models. However, a large body of empirical research has shown that an increase in unemployment may increase or decrease crime. By incorporating the return to crime into standard economic models, this paper shows that an increase in unemployment, as in recessions, decreases the opportunity cost of crime and the return to crime as well. As a result, the effect of unemployment on crime is ambiguous and depends on the apprehension rate. An increase in the unemployment rate tends to decrease the crime rate at lower apprehension rates, but to increase it at higher apprehension rates. An increase in the generosity of unemployment insurance benefits does not necessarily reduce the crime rate, and the effect of more generous unemployment insurance on crime depends again on the apprehension rate.