The 35-year-old defenseman was an unrestricted free agent. He had nine points (one goal, eight assists) in 74 regular-season games last season and no points in 13 Stanley Cup Playoff games for the Colorado Avalanche, who won the Cup.
"Jack provides the team with a strong veteran presence, good size (6-foot-1, 227 pounds) and a competitive edge," Blackhawks general manager Kyle Davidson said. "We're excited to have Jack join the organization and, coming off a Stanley Cup championship last year, he will strengthen our defensive group."
Selected by the Carolina Hurricanes with the No. 3 pick of the 2005 NHL Draft, Johnson has 312 points (72 goals, 240 assists) in 1,024 regular-season games for the Avalanche, New York Rangers, Pittsburgh Penguins, Columbus Blue Jackets and Los Angeles Kings. He has 21 points (five goals, 16 assists) in 43 playoff games.
The Blackhawks this offseason signed unrestricted free agent forwards Max Domi, Andreas Athanasiou and Colin Blackwell, and goalie Alex Stalock. They acquired goalie Petr Mrazek in a trade with the Toronto Maple Leafs and hired Luke Richardson as coach.
Forward Alex DeBrincat was traded to the Ottawa Senators and forward Kirby Dach to the Montreal Canadiens. Restricted free agent forwards Dylan Strome and Dominik Kubalik were not extended qualifying offers and signed with the Washington Capitals and Detroit Red Wings, respectively.
Chicago was 28-42-12 last season and has missed the playoffs in four of the past five seasons.
