10Death or serious harm caused in the course of violence of 2 or

10 Death or serious harm caused in the course of violence of 2 or more persons When a person dies or is found to be dead or to have suffered serious harm after 2 or more persons have used violence against him or his person and it is proved that the death or serious harm was caused as the result or in the course of that violence, but the evidence of the prosecution does not establish by whom it was caused, each of them is presumed either to have caused or aided the other or others to cause the death or serious harm until the contrary is proved if the violence used by him was of such a nature that it was likely to have caused, in the case of death, death or serious harm or, in the case of serious harm, serious harm.