A former employee of Bernard L. Madoff who started working for the convicted con man in the 1960s was part of the firm’s legitimate broker-dealer unit and didn’t know about the fraud at the investment advisory business, a lawyer told a jury, Bloomberg News reported yesterday. Daniel Bonventre, the operations chief who signed checks for Madoff’s securities firm and worked with its general ledger, was fooled by Madoff’s “depraved and pathological lies,” Andrew Frisch said today in federal court in New York. “Dan did what Madoff told him to do. That’s what the evidence will show. Dan believed Madoff like so many others.” Frisch was the first defense lawyer to present opening statements in the trial of five ex-employees who are accused of aiding Madoff’s $17 billion Ponzi scheme.