A communication method implemented by installing, in an automotive vehicle, an image sensing device, a data storage device for storing image data that has been captured by said image sensing device, a sensor for sensing impact, and a portable-terminal holding device in which a portable terminal is capable of being placed, wherein if impact has been sensed by said sensor, image data that has been stored in said data storage device is transmitted to the outside via said portable terminal placed in said portable-terminal holding device, and wherein if impact has been sensed by said sensor when said portable terminal placed in said portable-terminal holding device is in a communicating state, this communication is severed and the image data is transmitted to the outside.