Wai-Yin Wan

Are drug arrests a valid measure of drug use? A time series analysis

Purpose – The purpose of this paper is to determine whether trends in arrests for heroin, amphetamine‐type substances (ATS) and cocaine can be used as indicators of trends in the use of these drugs.Design/methodology/approach – The question was addressed using ARIMA models to analyse the relationship between arrests and emergency department (ED) admissions for narcotics, amphetamine type substances (ATS) and cocaine.Findings – Strong positive correlations were found for the narcotics and cocaine series between arrests and EDs in the same month (contemporaneous correlation) and between arrests in the current month and overdoses in earlier months (lagged correlation). The contemporaneous correlation between ATS arrests and EDs was slightly less strong than the lagged correlations at two and four months. A jump in ATS EDs, was followed by a jump in arrests in the same month and then two and four months later.Practical implications – Arrests for narcotics use/possession, ATS use/possession and cocaine use/pos...

Do drug seizures predict drug-related emergency department presentations or arrests for drug use and possession?

BACKGROUND Direct evidence of the effect of drug seizures on drug use and drug-related harm is fairly sparse. The aim of this study was to see whether seizures of heroin, cocaine and ATS predict the number of people arrested for use and possession of these drugs and the number overdosing on them. METHOD We examined the effect of seizure frequency and seizure weight on arrests for drug use and possession and on the frequency of drug overdose with autoregressive distributed lag (ARDL) models. Granger causality tests were used to test for simultaneity. RESULTS Over the short term (i.e. up to 4 months), increases in the intensity of high-level drug law enforcement (as measured by seizure weight and frequency) directed at ATS, cocaine and heroin did not appear to have any suppression effect on emergency department (ED) presentations relating to ATS, cocaine and heroin, or on arrests for use and/or possession of these drugs. A significant negative contemporaneous relationship was found between the heroin seizure weight and arrests for use and/or possession of heroin. However no evidence emerged of a contemporaneous or lagged relationship between heroin seizures and heroin ED presentations. CONCLUSION The balance of evidence suggests that, in the Australian context, increases in the monthly seizure frequency and quantity of ATS, cocaine and heroin are signals of increased rather than reduced supply.

Does parole supervision reduce the risk of re-offending?:

Although a large number of offenders are released to parole each year, little is known about the effectiveness of parole supervision in reducing re-offending. The few studies that have been conducted provide mixed results and, for the most part, have been unable to rule out the possibility of selection bias. The present study is the first to evaluate the effectiveness of parole supervision using propensity score matching techniques. It compares two groups of offenders, carefully matched in terms of factors likely to affect re-offending but differing in terms of whether they are supervised. The results suggest that parole supervision does reduce the risk of re-offending.