The most serious whistleblower claim from the KPMG scandal, that senior partners had illicitly accessed sensitive Lendlease board documents and kept them in a work locker, has been confirmed and led to the immediate expulsion of former chief operating officer, Eileen Hoggett.

“I can confirm that the ongoing investigation by external law firm Allens has uncovered new evidence that supports the whistleblower’s allegation that confidential client information was kept in a locker at KPMG’s Sydney office,” a spokesman for KPMG said.

“(KPMG Australia CEO John Sams) has taken immediate action to expel a partner from the firm,” the spokesman said, and confirmed it was Hoggett who was expelled.

“To say I am angry about this is an understatement. The conduct was totally unacceptable, and it is unacceptable that it has taken so long for us to get to this point,” Sams told partners on Friday afternoon.

KPMG said the investigations into the whistleblower allegations, which have thrown the firm into turmoil in recent months, remain ongoing. KPMG has updated impacted clients and the relevant regulatory and professional bodies.

Hoggett had already resigned over the scandal but had yet to leave the firm. She would have left with a significant retirement benefit - expected to exceed a million dollars - if that had proceeded.

Former KPMG boss Andrew Yates, who resigned over the scandal in May, received a retirement payment of $2.4 million, including $1.7 million in lieu of notice.

The scandal has also led to the resignation of former chair Martin Sheppard and other partners and is expected to trigger hundreds of staff cuts as clients and government expected withdraw their business with the firm.

The Lendlease allegation was at the core of the whistleblower claims that senior KPMG staff had shared data from blue-chip clients in order to win new business.

Hoggett has been approached for comment.

“It is very clear that, having provided our external auditor with all the normal access they require to Lendlease’s books and records, there has been a fundamental breach of trust whereby our auditor’s access to those books and records has been gravely misused,” Lendlease chairman John Gillam told a parliamentary hearing in June.

The company is preparing to dump KPMG as its auditor.

This week Macquarie dropped a potential bombshell on the KPMG scandal, telling shareholders the group is reviewing the embattled firm’s capability to deliver on the lucrative Macquarie audit tender it won last year, due to the exodus of senior staff over the scandal.

Macquarie has also instigated an external review of KPMG’s pursuit of the contract, which was valued at $69 million last year.

“The board has made formal inquiries of KPMG, and they include regarding KPMG’s ongoing capability and capacity to deliver the audit, given that some people have left that firm, and an assessment of the integrity of KPMG’s pursuit of our audit tender process,” Stevens said.

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