Michael Cohen announced a shift in his legal team Monday, ahead of a possible appearance before a congressional committee and ongoing cooperation with prosecutors from the U.S. Attorney's Office for the Southern District of New York and the office of Special Counsel Robert Mueller III.

Michael Monico and Barry Spevack, the name attorneys at Chicago's Monico & Spevack, have been brought on to represent Cohen. They replace Petrillo Guy & Boxer name attorney Guy Petrillo, who guided Cohen, President Donald Trump's former personal attorney, through plea processes with the New York and Washington, D.C., prosecutors' offices.

“We look forward to helping Mr. Cohen fulfill what he has told us is his only mission—to tell the truth as he knows it and to turn the corner on his past life and taking ownership for his past mistakes by cooperating as best as he can with all governmental authorities in search of the truth,” Monico and Spevack said in a joint statement.

The pair join attorney Lanny Davis, who has served as Cohen's spokesman. In a statement sent by Davis, Cohen said he welcomed Monico and Spevack and thanked Petrillo and his team.

Petrillo declined to comment.

Like Petrillo, Monico brings a prosecutor's insight to the team. He is a former assistant U.S. attorney in the Northern District of Illinois office. As a private attorney, Monico has handled substantial cases, including over 30 BP employees involved in the investigation of the Deepwater Horizon oil rig accident. He is a past president of the American Board of Criminal Lawyers.

Spevack has practiced with Monico for nearly four decades, focusing on federal and state criminal and civil appeals.

Cohen's need for legal resources will continue ahead of a three-year prison sentence set to begin on March 6. He was subpoenaed earlier this month to testify before Congress in February.

Cohen pleaded guilty in December to charges brought by Mueller's office of lying to that same body, as well as campaign finance violations, tax fraud and other charges brought by Manhattan prosecutors.

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