AA is only one of them.
None of the Big 5 accounting firms are any better. In the 90's I worked for a Kroll competitor and wore out the knees of my pants begging the CPA firms to do in depth investigations of their clients as part of the annual audit.
Every one of them admitted that it should be done but refused to do so because it exceeded their professional standards and practices and it would cause friction with their clients.
The good news, I hear business is good at my old company. Investigations are being done at a frenzied pace.
Too bad I couldn't close the deal. I might have been a hero and rich. :)