Alcohol, Other Drugs & Crime

The relationship between alcohol, other drugs and crime is extremely complex. Alcohol and other drugs may encourage aggression or violence by disrupting normal brain function, and according to the Disinhibition Hypothesis, for example, alcohol weakens brain mechanisms that normally restrain impulsive behaviors, including inappropriate violence.

However, most crimes result from a variety of factors (personal, situational, cultural, economical), so even when drugs are a cause, they are likely to be only one factor of many.

Offenders reporting being under the influence at time of offense
Offense Type	Federal	State	Both
All inmates	17%	31%	48%
Violent Offenses	25%	28%	53%
Homicide	18%	28%	46%
Sexual Assault	10%	20%	30%
Robbery	29%	38%	67%
Assault	20%	23%	53%
Other Violence	15%	24%	39%
Property Offenses	13%	35%	48%
Burglary	53%	40%	93%
Larceny / Theft	24%	37%	61%
Drug Offenses	16%	37%	53%
Public-order Offenses	12%	18%	30%

What the Evidence Means

The evidence indicates that drug users are more likely than non-users to commit crimes, often under the influence of a drugs and/or alcohol at the time the offenses are committed. As with offenders, many times it is the victims who are under the influence of alcohol and/or other drugs which increase the victims vulnerability to resist attacks.

The need for preventing alcohol and other drug problems is clear when the number of offenders who report being under the influence of drugs and/or alcohol at the time of an offense is alarmingly high; these numbers may be under-reported. Sexual assaults, for example, are under-reported; in 45% of lone-perpetrator rapes, offenders were perceived by their victims to be under the influence of alcohol and/or other drugs, only 30% of the offenders reported being under the influence of drugs and/or alcohol at the time of the offense.

Assessing the nature and extent of the influence of drugs on crime requires that reliable information about the offense and the offender be available, and that definitions be consistent; it is otherwise impossible to say quantitatively how much drugs and/or alcohol influence the occurrence of the crime, though, it is clear that a correlation exists.