I’ve wanted to read this since a book group I was in when I first moved to Boston read it. They read it before I joined and I thought it sounded interesting. So keeping with my theme of expanding my reading (and apparently reading a lot more nonfiction) I requested it from the local library.
Unfortunately, I wasn’t impressed. This book felt more like a really well written undergraduate research paper than a book than a published book (and they were typos too). Part of this I believe comes from the structure and subtitle of the book and the other part I think comes from the super-focused subject matter. I discuss both below, but before I get to that I do want to say that it was an interesting read and I found many of the stories compelling and the appalling way in which Harvard dealt with these students should be a black mark on their history and reputation regardless of the time period. Not only did the Secret Court expel a number of individuals they were so adamant in their beliefs that they expunged the records of some of the individuals completely removing them from Harvard University records and if any of those expelled attempted to get into another school or a job using their Harvard connection/credentials, Harvard had a policy of exposing explicitly why they were expelled and this continued into at least the 1970s.
For some reason, this novel just felt more real and better developed than Tenino’s first novel in this series. 
This is an example of a novel that could’ve been even better if they used a better copy editor, and this has nothing to do with the poor formatting of Amazon’s conversion process from the publisher provided copy. This is my honest response and I received no compensation.
This book is definitely a reader’s book, or maybe a writer’s book? I’m never really sure what the difference is, but either way it’s a tome that really pushes you to focus on what you’re reading as there are quite a few heavy philosophical arguments and references within the novel, and it pushes you to question what is and isn’t real with the protagonist acknowledging that he’s had previous stints in a mental institution and the varying ‘ghosts’ to which the title refers.