Also, in coming up with plots I look for classical dilemmas, interesting confrontations, ordinary people close to powerful epicenters. Political situations, lawyers, Washington, all allow for those creative elements. The Supreme Court is constantly the subject of both fiction and non-fiction books. Because people hear about it all the time, but know almost absolutely nothing about it. People know about the presidency and the congress, but those nine black-robed justices are a complete enigma.
Secrecy is always seductive, particularly when there is so much power concentrated in so few people.
And the people who have served on the court over the years tend to be fascinating characters in their own right. As a novelist, I found much material simply in studying past courts and justices. As the Constitution says, the Court is an equal branch of government. And many of the decisions they make don't always have much to do with justice between the two parties in a case, as ironic as that sounds. I find that incredibly intriguing and think others will as well.