I've been giving more thought to the Clean Power Plan leak. I keep coming back to the fact that this set of documents is a decade old. Obviously, one or more people have been sitting on these seven memos for a decade. These records could have been given to the New York Times at any time over the past five years or so--around when the "shadow docket" panic began. Why now?
Moreover, whoever decided to keep these seven memoranda a decade ago likely did not anticipate how singularly important the Clean Power plan ruling would become. Hindsight is always 20/20. The more likely scenario is this person retained many documents. I can only imagine that more documents may be coming from this source.
I do not think that the person who retained these documents is an outlier. It is far more likely that many people at the Court have retained confidential documents over the years. These records may have long collected dust in file cabinets and banker boxes, but are now likely being dusted off.