So he was, and as I told Kerne above, on second thought that suspicion dawned on me, too. It would explain why Justin stops the confession when Dolan asks Iris to elaborate on her motives - the confession has to sound like his, after all.

Plus Justin doesn't really need Tommy Dolan anymore - the radio show is established. And with Dolan knowing so much, it would be an excellent opportunity to get rid of him while simultanously exculpating Iris. I wonder whether the fact Norman was present when Dolan told Justin he followed Iris, etc., will be relevant?