How does Gerald L. Posner use imagery in Case Closed: Lee Harvey Oswald and the Assassination of JFK?

Example of Imagery:

"When Marina visited him, however, she felt his eyes betrayed is guilt. She knew that if he had been innocent, he would have demanded his immediate freedom and complained to the highest officials. His compliance, coupled with his assurance that he was not being mistreated, added to her feeling he had committed the crime"