Introduction

Drugs and crimes are the most serious topics in today's time. Three models have been proposed to analyse the connection between drugs and crime. The first model suggests that drug-induced effects can lead to criminal behaviour. The second model highlights economic motives, where individuals commit crimes to fund their drug habits. The third model, known as the systemic model, suggests that crime among drug users is linked to the illegal drug market. Goldstein acknowledges these models but also recognizes that factors beyond drug use may contribute to criminal activity. Essentially, there are three basic models for explaining the relationship between drug use and crime: substance use leading to crime, crime leading to substance use, or both being influenced by common causes (Powell, 2011). Substance use can lead to crime due to drug effects, economic incentives, or systemic violence associated with the drug market. Various biological and neuropsychological mechanisms have been proposed to explain how drug use increases the risk of violence, with chronic use of certain drugs like marijuana, opiates, and amphetamines being linked to violent behaviour. However, the evidence regarding cocaine, PCP, and LSD's association with violence is less conclusive. Additionally, drug and alcohol use may interact to influence violent behaviour.

The economic motivation model suggests that drug users resort to criminal activities like robbery and burglary to finance their drug addiction (Hassan et al., 2022). Studies on heroin addicts support this idea, showing a correlation between changes in drug use frequency and crime rates, particularly property crimes. The systemic model asserts that the drug trade is intertwined with violent crime, leading to disputes over territory, enforcement, and transaction-related offenses such as robberies and assaults (Hassan et al., 2022). This model likely explains much of the violence associated with illicit drug markets, including drug-related homicides. Crime leading to substance use proposes that individuals prone to deviant behaviour may be drawn to social settings where heavy drinking and drug use are prevalent. For instance, income from criminal activities like robbery may facilitate drug acquisition, reinforcing drug-related behaviour. It's also suggested that aspects of the criminal lifestyle, such as sporadic employment and mobility, may contribute to substance abuse. Additionally, some individuals may use drugs to self-medicate or justify their deviant actions. It's possible that both models are valid, with substance use and crime reinforcing each other in a reciprocal relationship (Jeffris and Titus, 2000).

The common cause model suggests that substance abuse and crime are linked because they share common factors like genetic traits, antisocial personality disorder, and family history of alcoholism (Powell, 2011). Additionally, factors such as poverty, social support, peer influences, and unstable employment contribute to both drug abuse and criminal behaviour. Growing up in an environment where drug use is prevalent, especially among parents, increases the risk of addiction in children. Environmental factors like living in poor, densely populated, and racially segregated neighbourhoods contribute to higher rates of violent crimes and delinquency (Hassan et al., 2022). Alcohol and certain drugs, like benzodiazepines, are associated with increased risk of violent behaviour, while others, like cannabis, may lead to specific methods of suicide. Drug use by perpetrators during assaults increases the likelihood of more severe violence and injury to victims. Some drugs, particularly potent benzodiazepines like flunitrazepam, can induce aggressive behaviour and memory loss, leading to extreme acts of violence with no recollection afterward. Drugs are directly related to crime through their illegal possession, distribution, and associated illegal activities like drug trafficking (Lundholm, 2013).