Character Role Analysis
For much of the book, Judge Ford is the adult voice of reason and logic. Turtle may approach the game with excitement and an eye towards cash flow, but the Judge, who's both careful and cynical, decides to conduct a serious investigation.
Let's not forget she's one of the only characters to have gone up against Westing in a game of strategy before. While she's working to solve the case for herself, the Judge works as a guide for us readers, explaining clues, collecting background information, and building a chain of devastating evidence against Westing's case.
She takes the game almost more seriously than anyone, and perhaps that's her problem: ultimately, she's so worried about protecting Mrs. Westing that she forgets she's still playing a game, and her opponent's strategy is still in play.