Who is Merle Davis from The High Window and what is their importance?

Merle Davis is Mrs. Murdock's secretary. Mrs. Murdock bullies Merle in public, but she treats her kindly in private. Merle is the former secretary of Horace Bright, who once made a pass at her. When Mrs. Murdock pushed Bright out his office window, she used Merle's emotional instability to convince her that it had been Merle who pushed him. When Merle discovers Vannier's body, she truly believes she killed him. Once Marlowe solves the case, he tells Merle she is not responsible, and then he personally escorts her back to her parents home in Wichita.