Bloomberg is reporting that a yet-to-be-released internal JPMorgan Chase (NYSE: JPM) report lays at least part of the blame for last year's London Whale trading debacle at the feet of the bank's silver-haired CEO. Say it ain't so, Jamie.

To release or not to release
According to Bloomberg, the report takes issue with Dimon's "oversight" of JPMorgan's chief investment office, where the trading blunder occurred.

The report is also critical of Ina Drew, who ran the chief investment office, and Doug Braunstein, the bank's former chief financial officer. Drew resigned her position in May of last year, while Braunstein was replaced as CFO at the beginning of this year.

The report was to be presented today to JPMorgan's board, which is expected to vote on whether to release it to the public tomorrow along with the bank's quarterly results. 

Nothing to see here, folks
Undoubtedly, there's plenty of blame to go around for the London Whale, a $6 billion-plus mistake for the country's biggest bank. How exactly does a $100 billion derivatives bet go unnoticed until it's too late?

Ina Drew ran the U.K. office where Bruno Iksil, the London Whale himself, actually worked, and she already fell on her sword. Braunstein is gone as CFO. And Dimon spent 2012 doubling down on risk and shaking up top management in the wake of the botched trade. For good measure, JPMorgan is also suing Iksil himself, along with Javier Martin-Artajo, Iksil's direct supervisor, over the incident. (Neither is with the bank any longer). 

Dimon is famously a control freak and completely obsessed with risk. It was this obsession that kept the superbank from the worst excesses of the financial crisis. He's still, almost unquestionably, the best risk manager in banking. Does he have to take a share of the blame for the London Whale, at least as captain of the ship? Yes. But for a ship as big as JPMorgan Chase to run smoothly, it needs a tip-top crew as much as it needs a tip-top captain.

We'll have to wait and see what the report says tomorrow, if it's even released, but I'm not holding my breath over whether it has anything game changing to reveal. The London Whale took a lot of people to bring in, but it also took a lot of people to set loose.