In To Kill a Mockingbird, why does Scout quiz Atticus about his visit to the Radleys' house?
To Kill a Mockingbird exposes many of the injustices that exist and the tragic consequences that result when people judge others and discriminate against them. Scout, Dill, and Jem have always been fascinated by the Radley family, and they are curious to the point of distraction about what they think Boo Radley may or may not have done. From all the talk in Maycomb, the Radleys have become "a neighborhood legend," and the children describe Boo as "the malevolent phantom" (chapter one) as a result of all the talk. Jem's vivid description of Boo satisfies the children's most graphic imaginings:
About six-and-a-half feet tall ... dined on raw squirrels and any cats he could catch... His hands were bloodstained... There was a long jagged scar that ran across his face; what teeth he had were yellow and rotten; his eyes popped, and he drooled most of the time.
The children even wonder if Boo is still alive or if he "died years ago, and they stuffed him up the chimney" (chapter five). Therefore, it is not surprising that Scout has a morbid curiosity of anything related to the Radley family. When Mrs. Radley dies, Scout wonders if her death had anything to do with Boo, and she is disappointed to discover that Mrs. Radley "died of natural causes" (chapter eight).
When Mrs. Radley dies, Atticus goes to the Radley home, no doubt to pay his respects and offer assistance--a decent, neighborly thing to do. When he returns, he tells Jem and Scout that Mrs. Radley died of natural causes, which surprises and disappoints them. They were convinced that "Boo had got her at last." At Jem's urging, Scout finally asks Atticus if he had seen Boo while inside the Radley house. Her father's response makes it clear he does not wish to discuss his visit further:
Atticus looked sternly around his newspaper at me: "I did not."
Jem keeps Scout from asking any more questions, knowing that Atticus continues to disapprove of their obsession with Boo Radley. Scout has to be "restrained" from peppering her father with questions about what he saw inside the Radley house because he had just returned from behind "enemy lines" and could report what she and Jem could only imagine. Because pursuing the truth about the Radley home and its inhabitants was forbidden by Atticus, the children's fascination was only heightened. Scout tries to get information from her father, even though he has made himself clear on the subject, just as she had tried to get information about the Radleys from Miss Maudie.