beginning excerpt:

By William K. Rashbaum, Ben Protess and Jonah E. Bromwich

• Feb. 18, 2021Updated 7:34 p.m. ET

As the Manhattan district attorney’s office steps up the criminal investigation of Donald J. Trump, it has reached outside its ranks to enlist a prominent former federal prosecutor to help scrutinize financial dealings at the former president’s company, according to several people with knowledge of the matter.

The former prosecutor, Mark F. Pomerantz, has deep experience investigating and defending white-collar and organized crime cases, bolstering the team under District Attorney Cyrus R. Vance Jr. that is examining Mr. Trump and his family business, the Trump Organization.

The investigation by Mr. Vance, a Democrat, is focused on possible tax and bank-related fraud, including whether the Trump Organization misled its lenders or local tax authorities about the value of his properties to obtain loans and tax benefits, the people with knowledge of the matter said, requesting anonymity because of the sensitive nature of the investigation. Mr. Trump has maintained he did nothing improper and has long railed against the inquiry, calling it a politically motivated “witch hunt.”

In recent months, Mr. Vance’s office has broadened the long-running investigation to include an array of financial transactions and Trump properties — including Trump Tower on Fifth Avenue in Manhattan, various Trump hotels and the Seven Springs estate in Westchester County — as prosecutors await a ruling from the United States Supreme Court that could give them access to Mr. Trump’s tax return.

The prosecutors have also interviewed a number of witnesses and have issued more than a dozen new subpoenas, including to one of Mr. Trump’s top lenders, Ladder Capital, the people with knowledge of the matter said.

In addition, investigators subpoenaed a company hired by Mr. Trump’s other main lender, Deutsche Bank, to assess the value of certain Trump properties, one of the people with knowledge of the previously unreported subpoenas said [....]