Who is J.D. Randall from A Case of Need and what is their importance?

J.D. Randall is Karen's father. He is a callous man, who seems to be more intent on protecting his family than in getting to the bottom of the truth of Karen's death. The author makes special note of the fact that J.D. is a brilliant surgeon, who is back in the operating room, performing heart surgery, the day after Karen's death.