In the novel Hoot by Carl Hiassen, why is Roy suspended from riding the bus?

In Chapter 1 of Hoot, Roy is riding the bus to school on a Monday morning. An older boy named Dana is bullying Roy by smashing his face against the bus window and squeezing Roy's head with his fingernails. As Roy's face is pressed to the glass of the window, he sees a boy running barefoot outside the bus. Filled with curiosity, Roy watches as the boy gracefully speeds off and away down the street and through several private yards. Throughout the week at school, Roy continues to think about the running boy. We later learn that this boy is known as "Mullet Fingers."
In Chapter 2, Roy is riding the bus and sees the running boy again, and this time makes a move to leave the bus to follow him. He is stopped, however, when Dana grabs the back of his shirt. When Dana does not let go, Roy punches him in the nose and runs off the bus. He now runs both in flight from people chasing him and in pursuit of the running boy.
Later on, Roy meets with the vice-principal regarding his fight with Dana on the bus. The bus driver did not see that Dana instigated the fight, so only Roy is being punished. Roy's punishment is a two-week suspension from riding the bus. He also has to write an apology letter to Dana.
https://www.nytimes.com/2002/11/17/books/chapters/hoot.html