For a murder, the "mens rea" is that of malice aforethought, a deliberate and sometimes premeditated killing. But the larger percentage of deaths result from situations where there is either no intention to injure another, or only an intention to inflict less serious injury. The need is therefore to be able to distinguish between those who happened to be present when another died accidentally or through misadventure, and those who have contributed to the death in a way that makes them criminally rather than merely morally responsible. For example, suppose that A, an expert in kayaking, organises an outing for local children who are learning the sport. They travel to a large lake but, after an hour of paddling, they are overtaken by a violent storm and some of the children drown despite all wearing life-preservers. If all the kayaks, paddles and ancillary equipment are shown to have been in good condition, the storm had not been forecast by the meteorological services, and it was reasonable for these children to undertake this type of outing given their level of skill/swimming, A will not have liability. But if many of the children were too inexperienced and/or a storm had been forecast, A might well be found liable by a jury.