After initially saying that he did not know how the lawyers were chosen to represent Ms. Hunter and Mr. Young, Mr. Baron acknowledged that he might have played a role.

The revelations of ties among the lawyers emerged through public records and interviews with people close to Mr. Edwards and Ms. Hunter, which suggested that their affair went on longer than Mr. Edwards admitted and that the effort to conceal it by Mr. Edwards’s inner circle was much more extensive than has been reported.

The review found that Mr. Edwards’s political action committee went to unusual lengths to make a final $14,000 payment to Ms. Hunter’s film company months after its contract with the committee had ended. The payment was issued while the committee was short on cash and could pay its bills only after receiving thousands of dollars from Mr. Edwards’s presidential campaign and donations from four people, including Mr. Baron’s wife.