Some of the more extensive harms and costs to society associated with the i
llicit opiate use problem arise out of users' involvement in criminal activ
ity. Little is known regarding the extent and nature of illicit opiate user
s' criminal involvement within the specific Canadian context. This paper pr
esents data concerning the criminal activity and criminal justice system in
volvement of a sample of 114 untreated illicit opiate users in Toronto on t
ile basis of self-report data, including such variables as illegal income,
types of offenses, and criminal justice history. The data support internati
onal research results that criminal activity is highly prevalent among illi
cit opiate users, and that this activity consists primarily of property and
drug-related offenses for income-generating purposes. Involvement in viole
nt offenses is very limited, Implications of these findings on social polic
y, Law enforcement, and addiction treatment are discussed.