Taft Stettinius & Hollister announced a merger with Michigan-based full-service law firm Jaffe Raitt Heuer & Weiss, P.C., effective Dec. 31.Taft, which reported 117 attorneys this spring in its Chicago office, announced the merger Sunday. It noted Jaffe will add about 120 attorneys representing more than 25 practice areas to its roster.Jaffe, founded in 1968, is the seventh-largest law firm in the Detroit metro area, with offices in Detroit and Southfield.“Jaffe is starting a new, modern chapter by joining …