The bond rating agencies are where the IRS and SEC ought to be investigating. Bond sales are supposed to be federally regulated, are they not?
Here's an example of their "A" rating assigned to CDD District 5 built in 2002:
Fitch Rates Village CDD No. 5 (FL) Special Assessment Bonds 'A'; Outlook Stable | Business Wire
"CDD No. 5 is an independent municipal entity with a representative board elected by residents. Fitch believes the district's independent governance structure insulates it from a recent tentative IRS finding that the commercial Village Center Community Development District (VCCDD) is not a 'political subdivision' of the state."