User blog comment:Epzilon/Eleven Supernova (Continued)/@comment-3403804-20151024004805/@comment-2089817-20151024012359

Seireitou has a tendency of doing a lot of shady things. But you didn't hear it from me.

My understanding is that the Juusanseiza are basically the Soul Society's equivalent to the Wandenreich's "War Potentials". Individuals that are capable of shifting the tides of influence, reputation, and overall status of the Soul Society and perhaps even the Human World. Central 46 would feel a great need to keep these individuals in check. They are, at best, anomalies in the eyes of the Shinigami. Not all anomalies can end up being a hero like Ichigo. In fact, one such anomaly, Kugo Ginjo, ended up killing many Shinigami and could've even persuaded the man who killed Aizen to join his side if Ichigo wasn't the type of person who could be trusted. The point is, these unruly elements need to be kept under watch, and as Nanja said, I definitely see Soul Society trying to shore up their power by getting them on their side. Especially since the Four Heavenly Kings are pretty much gaining total control in the last couple years.