The practice appears to be unusual even in Mississippi, where lawmakers recently acted to limit when people can be jailed as they go through the civil commitment process. Sheriff’s departments in about a third of the state’s counties, including those that appear to jail such people most frequently, responded to questions from Mississippi Today and ProPublica about how they handle involuntary commitment. They said they seldom, if ever, take people who need mental health treatment from a hospital to jail. At most, said sheriffs in a few rural counties, they do it once or twice a month.