Pertaining to data collected by the Bureau of Justice Statistics: Two or more persons inflicting some direct harm to a victim. The victim-offender relationship is determined by the offender with the closest relationship to the victim. The following list ranks the different relationships from closest to most distant: spouse, former spouse, parent, child, other relative, nonrelative well known person, casual acquaintance, or stranger. (https://www.bjs.gov/index.cfm?ty=tda)