This is a difficult case. You must attempt to determine which of the people in the lunchroom killed Fannin. You will have to observe the details carefully. There is enough evidence to help you explain most of what happened. In working out the solution, answer the following questions (make sure you answer all questions for each number):
1. With what hand did the shooter fire the gun? What is the evidence? What is the warrant (rule)?
2. Did customers B, C, and D know each other? What are the evidence and warrants?
3. How do the three customers differ in their habits or ways of doing things?
What is the evidence and what is the warrant(s)?
4. Which set of footprints are Ernie's? What is the evidence? What is the warrant?
5. To whom do the set of footprints marked X belong? How do you know?
6. Who killed Fannin? How do you know?
1. The shooter fired the gun with their left hand. The evidence for this is that the bullet casing was on the left side of Fannin's body. The warrant (rule) is that when a person fires a gun, the bullet casing will eject in the direction opposite of their dominant hand.
2. Customers B, C, and D did not know each other. The evidence for this is that Customer B was reading a book, Customer C was looking at the ceiling, and Customer D was doodling on a napkin. They were all engaged in different activities and did not acknowledge each other. The warrant is that when people know each other, they usually interact in some way, such as talking or making eye contact.
3. Customer B reads a book, Customer C looks at the ceiling, and Customer D doodles on a napkin. The evidence for this is their different habits observed during the lunch break. The warrant is that people have different ways of occupying themselves during free time, based on their individual preferences and habits.
4. Ernie's footprints are the ones marked Y. The evidence for this is that Ernie's shoes were covered in mud, which matches the footprints marked Y. The warrant is that someone's footprints will match their shoes' pattern and the dirt or material on their shoes.
5. The footprints marked X belong to the customer seated at the counter. This is known because the footprints lead from the counter to the front door, indicating that the person at the counter left in a hurry. The warrant is that footprints can provide clues about a person's movement and actions.
6. Customer D, Ernie, killed Fannin. The evidence for this is that Ernie's footprints lead to the spot where Fannin was shot. Additionally, the gun was found in Ernie's backpack. The warrant is that physical evidence, such as footprints and possession of the murder weapon, can help identify the killer.