When a violent encounter happens at a church, it’s often a surprise—and 90 percent of the time, the violence doesn’t stop until the perpetrator decides to stop, according to statistics collected by church security expert Carl Chinn. Sometimes these violent events unfold too quickly for staff or law enforcement officials to respond.

While quick, in-the-moment responses are important in these situations, it is also crucial for church staff to watch for signs of violence or strained relationships among church members on a daily basis. In 2016, 11 of the 47 murderous attacks at churches and ministries had the same culprit: domestic violence. (Chinn tracks these data using news reports and labels the cause “domestic violence” when the victim and killer were co-habiting, married, or related.) In such cases, the church tends to let the ball drop long before violence turns deadly.