[Kevin]

From a non-legal standpoint, I think Delta Zeta appears to be on its face hypocritical.

On the one hand, they had no problem giving their own members the boot without any sort of process which made sense to anyone.

On the other hand, they're complaining when Depauw, a private school seems to have done exactly the same thing to Delta Zeta.

Legally, I know I'd be misstating the theory, but it seems to me that some species of equitable estoppel might operate as a strong defense for the University.

That aside, also legally, I don't believe that (absent a contractual duty) Depauw has any obligation to follow its own policies with regard to any matter. Those policies may provide some sort of intra-organization decision-making framework, but policies of private organizations generally do not operate as contractual obligations to the outside world.