As prosecutors in Manhattan weigh whether to charge Donald J. Trump with fraud, they have zeroed in on financial documents that he used to obtain loans and boast about his wealth, according to people with knowledge of the matter.
The documents, compiled by Mr. Trump’s longtime accountants and known as annual statements of financial condition, could help answer a question at the heart of the long-running criminal investigation into the former president: Did he inflate the value of his assets to defraud his lenders?
In recent weeks, prosecutors in the office of the Manhattan district attorney, Cyrus R. Vance Jr., have questioned one of Mr. Trump’s accountants before a grand jury as part of their examination of the financial statements, said the people with knowledge of the matter. Prosecutors also interviewed his longtime banker, another person said.
If the prosecutors seek an indictment, the case’s outcome could hinge on whether they can use the documents to prove that a defining feature of Mr. Trump’s public persona — his penchant for hyperbole — was so extreme and intentional when dealing with his lenders that it crossed the line into fraud.
Whenever Mr. Trump needed a loan, he would provide potential lenders with the statements, which contained optimistic projections about the value of his real estate business as well as sweeping disclaimers noting the numbers’ limitations.
Mr. Vance’s prosecutors found that the accountants who put together the statements relied on underlying information provided by the Trump Organization, Mr. Trump’s family business, according to the people with knowledge of the matter, who were familiar with the questions prosecutors asked and spoke only on condition of anonymity because they were discussing confidential testimony.
The prosecutors, working with the office of the New York State attorney general, Letitia James, have examined the possibility that Mr. Trump and his deputies at the company cherry-picked favorable information — and ignored data that ran counter to it — to essentially mislead the accountants into presenting an overly rosy picture of his finances.
While the numbers could implicate Mr. Trump, disclaimers in the statements that the data had not been audited or authenticated could help his defense, underscoring the challenge that prosecutors face as they grapple with whether to charge the former president.
A spokeswoman for Mr. Trump’s accounting firm, Mazars USA, declined to comment beyond saying that it could not discuss its clients or its work for them without their consent, and that Mazars remained “committed to fulfilling all of our professional and legal obligations.”
Jerry D. …….