Mr. Fitzgerald said Mr. Siskel was “relatively soft-spoken” and a gifted writer, skills that he expected would serve him well when responding to requests from Republicans.
Several of Mr. Siskel’s allies said he had a seasoned understanding of where established legal precedents are with congressional investigations targeting the White House — a signal, they said, that Republicans may have to clear a high bar to review any of the information they may ultimately decide to seek from the president.
Mr. Siskel is no stranger to partisan fights, but he is also known for leveling with his clients, people close to him say. He most recently worked as a chief legal officer for Grosvenor Holdings, a Chicago-based investment firm. At the White House, he will lead a crew of over 40 lawyers who most recently served under Stuart Delery, who announced last month that he was leaving the post.
Mr. Siskel, who did not respond to a request for comment, was a White House lawyer focused on congressional oversight issues during the Obama administration. He earned a reputation as a crisis manager when he helped lead the administration’s effort to counter Republican investigations into the Benghazi terrorist attack, a lengthy case that uncovered no new evidence against its main target, former Secretary of State Hillary Clinton.
Mr. Siskel was deputy White House counsel when he left for private practice at the law firm WilmerHale, where he was recruited to work for Rahm Emanuel, then the mayor of Chicago. Under Mr. Emanuel, Mr. Siskel served as corporation counsel, overseeing dozens of lawyers and fighting legal claims against the city. Mr. Emanuel praised Mr. Siskel as having a sharp understanding of the politics surrounding legal decisions.