Alternative path for Markopolos

Throughout the story of Markopolos's whistle-blowing, he is in a continual, frustrated struggle to get the SEC to act. The thought kept occurring to me that he might have been able to persuade the FBI to act on the basis of a simple fraud complaint, because Madoff was not actually making the trades he claimed he was.

My understanding is that, if there is fraud, then the New York State or even a local NYC bunko squad could have charged him, as well as the FBI for interstate.

Or does the involvement of securities in the fraud limit the enforcement of law to the SEC?
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