Facing multiple sexual misconduct allegations and fearing his career as an entertainment titan was over, Leslie Moonves, the chief executive of CBS, destroyed evidence and misled investigators in an attempt to preserve his reputation and save a lucrative severance deal, according to a draft of a report prepared for the company’s board.

The report, by lawyers hired by the network, says the company has justification to deny Mr. Moonves his $120 million severance. Mr. Moonves reigned as one of Hollywood’s most successful and celebrated executives for decades before being forced to step down in September after allegations by numerous women.

The report, a copy of which was reviewed by The New York Times, says Mr. Moonves “engaged in multiple acts of serious nonconsensual sexual misconduct in and outside of the workplace, both before and after he came to CBS in 1995.” The report includes previously undisclosed allegations of sexual misconduct against him.

The lawyers who conducted the inquiry wrote that they had spoken with Mr. Moonves four times and found him to be “evasive and untruthful at times and to have deliberately lied about and minimized the extent of his sexual misconduct.”