JPMorgan Chase’s decision to stop doing business with Jeffrey Epstein became easier after there was no one at the bank to advocate for him, a top executive at the nation’s largest lender said in a deposition taken in connection with two lawsuits arising from the institution’s nearly 15-year relationship with the disgraced financier.

Mary Erdoes, head of JPMorgan’s asset and wealth management division, said in a March deposition reviewed by The New York Times that she decided to dismiss Mr. Epstein as a client in summer 2013 because of concerns about repeated large cash withdrawals from his many accounts with the bank.

She said an annual review of Mr. Epstein’s accounts took place several months after James E. Staley, who had been a top private banker at JPMorgan and the main advocate of Mr. Epstein, left the bank in January 2013.

Ms. Erdoes said Mr. Epstein, who became a registered sex offender after a 2008 guilty plea in Florida to soliciting prostitution from a teenage girl, was considered a “high risk client.” She said she hadn’t known when Mr. Epstein was labeled such.

“Mr. Staley was Mr. Epstein’s advocate in the bank and was the senior relationship manager for Mr. Epstein,” Ms. Erdoes said. “And without someone there advocating for Mr. Epstein and the situation that I viewed, I was exiting Mr. Epstein.”

A decade after JPMorgan ended its dealings with Mr. Epstein, and nearly four years after his suicide while he awaited trial on federal sex trafficking charges, the issue of what executives at the nation’s biggest bank knew about Mr. Epstein’s abuse of dozens of teenage girls and young women is critical in the lawsuits facing the bank.