Mark Olson has announced he will step down as chairman of the Public Company Accounting Oversight Board, which he has headed since July 2006, according to media reports. His resignation takes hold on July 31. It's unclear what, if anything, should be read into this. Clearly, the board is at a critical moment in its short history.

The Supreme Court has decided to take up a case that questions the constitutionality of the board. The fear among Sarbanes-Oxley supporters is that the a ruling that the board is not constitutional will open a movement to rethink the validity of the board and Sarbanes-Oxley, in general. But why that should prompt his resignation is unclear. It may be that Olson was appointed by Christopher Cox, then-chairman of the SEC. There's a new leader now, with a different agenda, but that alone should not be an issue for the independent board. Perhaps we should take it at face value, and believe Olson's explanation that his decision was entirely personal. 

For more:
- here's an AP article

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