http://www.law360.com/articles/419166/the-most-unlikely-fina...
I suspect the real reason is the quote at the bottom of the page:
"Vance — and by extension, New York’s entire state and federal regulatory regime — gain credibility for their tough stance against an allegedly sketchy institution. The mere indictment builds political capital, regardless of whether there’s any factual basis for their claims."
In other words: this case was brought to Enhance Vance's stature, not because of the gravity of the case.
Yu's supervisor was as far as I understand the case the only other person that should have faced charges, the rest is either operating on instruction from Yu or simply did not know about it and did the right thing once the situation came to light.
Yu's supervisor should have probably caught this in an earlier stage, it went on for too long.
It does not look like a single "rogue employee" but multiple employees in the department. Of course that doesn't mean anyone at the top is to blame, but one can see why the prosecutor would draw that inference.
> What HSBC did went - as far as we can see from the outside - right to the top and required a lot more than a rogue employee.
What about HSBC went to the top? The only thing from the indictment that was a policy from the top was not classifying Mexico as a "high risk" country for money laundering controls purposes. There wasn't even a "single loan officer . . . [who] joined the prosecution against the bank only to relieve the pressure on himself" willing to testify that a higher up made that classification decision with specific intent to profit from money laundering.
If there had been a witness like Mr. Yu in the HSBC case, the government would've settled for a lot more than it did.