Jenner & Block has appointed Thomas J. Perrelli as its new firm chair, effective March 5.Perrelli, who is based in the firm’s Washington, D.C., office, succeed Craig C. Martin, who will be remaining with the firm’s Chicago office but is stepping down from the role to “focus on his practice and community engagement.”Perrelli will become the fifth partner to chair the firm in its more than 100-year history. Martin will remain a member of the firm’s policy committee.“On behalf of the …