"The third person narrator, instead of being omniscient, is like a constantly running surveillance tape"

This quote by Andrew Vachss is referring to the use of a 3rd individual narrator in literature. Rather of the narrator being omniscient, or all-knowing, Vachss is recommending that the narrator is more like a surveillance tape, continuously running and taping occasions as they occur. This kind of storyteller is restricted in its understanding, just able to report what it sees and hears. It is not able to provide insight into the thoughts and sensations of the characters, or to supply any kind of judgement or viewpoint on the events that are happening. This kind of narrator is often utilized to develop a sense of realism in a story, as it is more reflective of how we experience the world in our everyday lives. It can also be used to produce suspense, as the reader is just able to find the truth of the story as it is exposed to the narrator.