The stakes are high, not only for Executive Director Carl Greene, but potentially for the city of Philadelphia.
Only Action News was there as the team of federal auditors arrived to start digging through the books at PHA.
They are working with the FBI and will be looking at much more than just the sexual harassment claims against executive director Carl Greene.
The auditors will be sifting through every aspect of PHA management and its handling of hundreds of millions of dollars of federal money.
The FBI will be looking into possible criminal activity as part of a grand jury investigation.
They've issued a search warrant for specific documents.
An internal letter to PHA employees obtained by Action News spells out what the feds are looking for.
They're specifically interested in a half dozen shadow organizations created within PHA, that, among other things, appear to have collected money from contractors and employees.
The PHA board is also conducting its own investigation.
Board member Patrick Eiding says they want to know who else, other than Carl Greene, was involved in what appears to be a cover-up of insurance payments to settle four sexual harassment claims against Greene.
And they want to know why the board was not kept informed.
Eiding says if even one of the claims against Greene turns out to be true, he will be fired.
Mayor Nutter is worried the city might find it harder to get its share of federal low income housing dollars if the HUD auditors uncover evidence of mismanagement.
"I'm very, very concerned about potential jeopardizing of any funding coming into Philadelphia," Nutter said.
While the investigations are underway, Carl Greene remains locked out of the building with no access to documents on his computer. His lawyer says he's out of state undergoing medical treatment for stress.