A distributor device and a method for a data network in a motor vehicle includes a number of first communications interfaces which can be coupled to communications partners of a first priority and a number of second communications interfaces which can be coupled to communications partners of a second priority. The second priority is lower than the first priority. The distribution device further includes a coupling device configured to couple together the first communications interfaces and the second communications interfaces, such that they communicate together, and a monitoring device configured to monitor communication along the second communications interfaces, and in the event of a communications error on one of the second communications interfaces to disconnect at least the first communications interfaces from the corresponding second communications interface so as to interrupt the communications.