Marijuana may be a contributor to marital bliss. At least, that is what one study explains, arguing that couples that smoke the drug are less likely to report marital violence than couples that do not smoke marijuana.

Conducted by researchers from Yale University, Rutgers and SUNY Buffalo, the study followed 634 couples in the first nine years of their marriages to determine how intimate partner violence (IPV) manifested among couples that used marijuana.

Published in the journal Psychology and Addictive Behaviors, the study found: "In fully adjusted models, we found that more frequent marijuana use by husbands and wives predicted less frequent IPV ... perpetration by husbands. Husbands' marijuana use also predicted less frequent IPV perpetration by wives. Moderation analyses demonstrated that couples in which both spouses used marijuana frequently reported the least frequent IPV perpetration."

According to the Huffington Post, the study recruited couples who applied for marriage licenses in New York State between 1996 and 1999 and researchers followed up for the next nine years with mail-in surveys asking about each couples' marijuana use and its effect on IPV.

Researchers asked about each couples' consumption of marijuana or hashish "(defined as pot, weed, reefer, hash, hash oil or grass)," according to the Huffington Post, in the last year. They were also asked about whatever alcohol and other drugs they consumed.

The study found that instances of violence decreased when one or both partners partook in the consumption of the drug and only one instance was found to increase violence. "There was a significant positive association between wives' marijuana use and wives' IPV perpetration, but only among wives who had already reported IPV perpetration during the year before marriage," the study concluded.

The Washington Post reports that researchers hypothesized "marijuana may increase positive affect, which in turn could reduce the likelihood of conflict and aggression." However, another probable cause for lower cases of IPV could be that people high on marijuana are less aggressive due to their "blunted emotional reaction to threat stimuli."