It isn't called a peace pipe for nothing. New research backs up what most people would have probably guessed—that married couples who smoke pot tend to be less violent than those who don't, and that this is especially true when both partners toke up. In a study of 634 couples over a nine-year period, researchers at the University of Buffalo write in the journal Psychology of Addictive Behaviors that more frequent marijuana use (at least two to three times a month) predicts less frequent violence, and that even a husband who uses marijuana predicts less violence from the wife.
The study did not, however, look into whether marijuana use on a particular day impacts violence on that day—in other words, whether actually being stoned influences behavior. "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 ... conflict," one researcher says. They plan to investigate day-to-day use and behaviors before drawing "stronger" conclusions. (Earlier this summer, one man actually used 3-foot pot plants to attack his brother.)