Ty Cobb, a longtime Hogan Lovells partner based in Washington, D.C., has joined President Donald Trump's legal team as special counsel. His last day at Hogan Lovells will be July 30, the firm's chairman said in an all-firm email sent Friday afternoon.

The White House had not officially announced the appointment as of late Friday afternoon, and several leaders and a spokesman for Hogan Lovells did not respond to requests for comment. Cobb's email was set to an out-of-office auto reply Friday, saying he's "currently on travel."

The National Law Journal obtained a copy of the email written by Hogan Lovells chair Stephen Immelt announcing Cobb's departure from the firm and confirmed his move with two other sources.

Bloomberg News, which first reported Cobb's hire, said he would serve as "traffic cop, enforcer of discipline and public spokesman" for the president's legal team as it grapples with simultaneous congressional and Justice Department investigations into the Trump campaign s Russia contacts, which are consuming the president's politics more every day.

Cobb a relative of the baseball great of the same name will also work with outside lawyers representing others in Trump's inner circle, the report said. NBC News said Friday it had also confirmed Cobb's hire.

Members of the president's personal legal team include Marc Kasowitz, who this week was under fire after Pro Publica Inc. raised questions about his comportment; Jay Sekulow, who has primarily acted as a spokesperson for the president's case; and John Dowd, the combative Washington, D.C., criminal defense lawyer who retired from Akin Gump Strauss Hauer & Feld in 2015.

Cobb has worked on white-collar cases for more than three decades. He previously was on Hogan Lovells executive committee and ran various practices including white-collar criminal litigation, U.S. Securities and Exchange Commission enforcement and congressional investigations and hearings. Past clients include IBM, members of the Saudi royal family, a private oil company in Argentina, the insurance company American International Group Inc. and former Democratic National Committee fundraiser John Huang, who ultimately pled guilty in a felony campaign finance scandal.

The firmwide email from Immelt described how Cobb once ran and grew the firm's Denver office. It also noted that he has been based in D.C. since 2005, "although his colleagues and friends know that he has been working legal magic somewhere exotic more often than he has been in the office."