What is the importance of the Blackwell Island Insane Asylum in the novel, The Address?

Sara is mistakenly taken to the Blackwell Insane Asylum, which is close enough to the Dakota in New York City that she can see it on the horizon. The Asylum, with all women patients, is essentially a cruelly run prison, as patients are given limited things to do and are cruelly treated by "nurses" if they break any of the myriad of unrealistic rules. An investigative reporter justly damages the reputation of the Asylum when she goes undercover as a patient and witnesses the inhumane treatment.