SAN FRANCISCO (CBS SF) — A confidential memo between staff at the California Attorney General’s Office reveals that state investigators had questions over how President-elect Donald Trump’s nominee for Treasury secretary Steven Mnuchin handled foreclosures as head of a California-based real estate lender.

U.S. Senator Kamala Harris in 2013 — then as the California Attorney General — declined to file charges against OneWest Bank, and its CEO Mnuchin, despite state investigators’ strong recommendation to do so.

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Investigators state in a memo that they were concerned the bank had conducted “widespread misconduct” that led to unlawful expediting of residential foreclosures in California.

The California Reinvestment Coalition, which advocates for fair and equal access to banking and other financial services for low-income communities and communities of color released a statement after The Intercept first published the memo.

The coalition says that the memo shows evidence of “illegal foreclosure practices at OneWest Bank While Steven Mnuchin was CEO” and calls for a U.S. Senate investigation into the alleged violations before Mnuchin is sworn in as U.S. Treasury Secretary.

Kristin Ford, a spokeswoman for the California Attorney General’s Office did not say why the office declined to file charges, but instead told CBS San Francisco, “Investigations conducted by the attorney general’s office and internal deliberations are confidential in nature. A wide range of factors are considered in any decision about whether or not to bring charges against an entity or individual.”

The California Reinvestment Coalition says the memo, which was based on a preliminary investigation by the California Attorney General’s Office, raises new concerns about Mnuchin’s ethics.

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In the memo, the state investigators suggest that the bank hurt California homeowners.

“…OneWest’s false filings and unauthorized conduct in the course of the foreclosure process harmed homeowners by denying them timely and important information about their foreclosures and potentially shortening the amount of time they had available to find a way to become current on their mortgage obligations,” investigators state in the memo.

Many of the homeowners who were impacted resided in California, according to the memo, including some residing in the San Francisco Bay Area.

Investigators state that in Alameda and Santa Clara counties they identified a number of instances in which OneWest Bank allegedly conducted unlawful credit bids.

The memo also alleges that the bank backdated some legal documents with date that fell before the bank existed.

Furthermore, the memo states that with “the unlawful credit bidding OneWest claimed an exemption from the applicable city and county transfer taxes and no tax was paid.”

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By Hannah Albarazi – Follow her on Twitter: @hannahalbarazi.