Newly released internal bank documents show senior executives at JPMorgan Chase had serious doubts about the legitimacy of Bernard Madoff’s investment business more than 18 months before his Ponzi scheme collapsed. Despite repeated suspicions, the bank allowed Madoff to move billions of dollars of investors’ cash in and out of his Chase bank accounts right until the day of his arrest in December 2008. In one email, a high-level risk management officer for Chase’s investment bank wrote, “There is a well-known cloud over the head of Madoff” and “his returns are speculated to be part of a Ponzi scheme.” Lawyers have accused the bank of overlooking the warning signs in order to pursue profitable credit and derivatives deals with Madoff and his investors.