If he was scared how hard was it to get back in his car, and have dispatch call the house and tell the folks to put up that dog?
That's what normal folks do, but cops these days are selected for super dominant personality type, and this is cultivated further in academy and thereafter, i.e., their egos don't permit them to do anything that creates any impression other than total domination of whatever environment they find themselves in. Retreating from a dog would go counter to this.
