What is the importance of the White Tower in the novel, The White Princess?

The Tower of London is one of the main palaces the court stays in during the course of the novel. All of the major characters visit at some point; whether to be protected or incarcerated. For some, the mere threat of being locked away in the tower is enough to dissuade committing a crime. It is here that Elizabeth's brothers are killed by an unknown person, and where Teddie spends the entire novel up to his death.