A former Nixon Peabody partner, David Tamman, who in 2012 was sentenced to seven years in prison for conspiring to obstruct justice, altering documents, and abetting a client's false testimony, all in connection with an effort to cover up a client's Ponzi scheme, sued the firm for not paying for his legal defense. In September 2014, a California state appeals court declined to reject his claim. Nixon Peabody had argued that his suit violated the firm's First Amendment rights, but the court held that “the inclusion of allegations involving protected activity does not subject a claim to the anti-SLAPP statute where the protected activity merely preceded or triggered the lawsuit.”[40] Tamman's appeal, arguing that sentencing guidelines were incorrectly applied, was denied by the Ninth Circuit Court of Appeals on April 6, 2015.
In September 2009, Melissa Mahler was sued by the SEC for having engaged in insider trading when she was a Nixon Peabody associate in 2004. Mahler, who had left the firm in 2005 when her insider trading came to light, was charged with having bought 10,000 shares of a client's stock after learning of plans for a merger. The firm said that she had left “immediately after we learned that her personal conduct had come under regulatory scrutiny.