It seemed to me like Spectre was it’s own persona that is hosted by Corrigan. In fact, that’s basically how it was in the last big book he starred in before this, Gotham By Midnight, where Corrigan would basically have to solve the case and try to make things right before The Spectre would emerge and basically destroy everything in his righteous fury.
By the way, I would recommend that series for the people of this club, very fun stuff. The first arc had exquisitely creepy art from the famed Ben Templesmith. We also covered it at over at the World of Bats club last October, if you don’t mind a little promotion. 