What is Forensic Accounting Investment Analysis?

Forensic accounting investment analysis cannot be accomplished by simply reading publicly-available financial statements and looking for accounting issues.

Every investment analyst and portfolio manager already does that.

Forensic accounting is the in-depth analysis of internal financial documents (audit working papers, accounting ledgers, internal correspondence). These documents are only available as part of the discovery process in litigation matters, and are not available to the public.

How it this applied to investment research?