Married couples who smoke marijuana are less likely to engage in domestic violence, a new study from the University of Buffalo reveals. 

"These findings suggest that marijuana use is predictive of lower levels of aggression towards one's partner in the following year." lead investigator Kenneth Leonard, director of the UB Research Institute on Addictions, said in a press statement. "As in other survey studies of marijuana and partner violence, our study examines patterns of marijuana use and the occurrence of violence within a year period. It does not examine whether using marijuana on a given day reduces the likelihood of violence at that time."

This is one of the first studies that looked to clarify previous findings suggesting a link between domestic violence and pot-smoking couples. For the study, researchers examined 634 married couples during the first nine years of their marriage.

They found that the more frequently the husbands and wives used marijuana, the lower the level of intimate partner violence (IPV) perpetration by husbands. It also predicted less frequent IPV perpetration by wives.

"It is possible, for example, that -- similar to a drinking partnership -- couples who use marijuana together may share similar values and social circles, and it is this similarity that is responsible for reducing the likelihood of conflict," he said. "Although this study supports the perspective that marijuana does not increase, and may decrease, aggressive conflict, we would like to see research replicating these findings, and research examining day-to-day marijuana and alcohol use and the likelihood to IPV on the same day before drawing stronger conclusions."

The study was supported by a grant from the National Institute on Alcohol Abuse and Alcoholism to Leonard and a grant to Smith from the National Institute on Drug Abuse. Findings were published online in the journal Psychology of Addictive Behaviors.