In a recently published study in the journal Addiction, researchers from Bowling Green State University report evidence of an association between father's incarceration and substantially elevated risks for illegal drug use in adolescence and early adulthood.

The number of persons incarcerated in the United States has sharply risen over the past several decades, from about 250,000 in 1975 to 2,250,000 in 2006. So too has the number of children with incarcerated parents, particularly fathers. The consequences of father's incarceration for their children, families, and communities are of increasing concern to researchers, policy makers, and practitioners.

Using data from the National Longitudinal Study of Adolescent Health, a nationally representative sample of adolescents in schools in 1995, who were periodically followed into their early to mid-20s, this new study examined the association between having an incarcerated biological father and marijuana and other illegal drug use. Over 51% of young men, and almost 40% of young women, whose biological fathers had a history of incarceration reported using marijuana, compared to 38% and 28%, respectively, of comparable men and women whose fathers were never incarcerated. Youth with incarcerated fathers also exhibited elevated trajectories of marijuana usage that extended into their mid-twenties, compared to other youth whose marijuana use peaked at about age 20. Biological father's incarceration was also found to be associated with elevated use of other illegal drugs, such as cocaine, heroin, and methamphetamines.

Given that having a father in prison is an increasingly common event, this study's findings suggest that a substantial number of young people in the USA are at risk for drug use. Increased drug use is closely linked to a number of adverse outcomes, including illegal drug market activity, increased crime and incarceration rates, lost work productivity, and costly substance abuse treatment. "Long-term drug use may exacerbate many other problems faced by disadvantaged youth, including mental health issues, delinquency, dropping out of school, domestic violence and poverty," says the study's lead author, Dr. Michael Roettger, a Postdoctoral Fellow with the National Center for Family and Marriage Research. Roettger notes that "this is of particular concern within poor and minority communities where incarcerations are disproportionately located."

The researchers are careful to note, however, that this is a non-experimental study, and that the relationships observed are associations, and should not be taken to indicate a causal process. "Further research is needed to more fully examine if it is father's incarceration, or other closely related factors such as father's criminality, family histories of drug use, or stresses associated with family instability, that are driving these detrimental relationships" cautions Dr. Raymond Swisher, one of the study's co-authors. Danielle Kuhl and Jorge Chavez, also of Bowling Green State University, are also co-authors on the study.

The numbers show the potential size of the problem. In 2006, nearly 7.5 million children were estimated to have a parent currently in prison or on probation/parole. Expressed in terms of cumulative risk, 13% of young adults in the U.S. report that their fathers had spent time in prison during their childhoods.