A week after Rudolph Giuliani left the firm formerly known as Bracewell & Giuliani, the former New York City mayor and some of his former partners are exchanging barbs over his tenure at the firm and his departure.

On Jan. 19, Greenberg Traurig announced that Giuliani was joining its ranks, along with white-collar specialist Marc Mukasey. The 71-year-old Giuliani will chair the firm’s cybersecurity and crisis management practice and serve as a senior adviser to Greenberg Traurig executive chairman Richard Rosenbaum. Mukasey, 48, will co-chair the firm’s white-collar defense practice. In an interview last week, the two men said that they were attracted to Greenberg Traurig’s bigger global platform.