Choate, 37, spent the 2012 season with the Miami Marlins and the Los Angeles Dodgers. The left-handed reliever appeared in 80 games last season, striking out 38 in 38 and 2/3 innings with an ERA of 3.03.
The veteran joins an experienced St. Louis bullpen as its senior member. Edward Mujica, Mitchell Boggs, and Jason Motte all posted ERAs of less than 3.00 for the Cardinals in 2012.
The 6'1 pitcher from Florida State has played 12 major league seasons, posting a career ERA of 4.02. He has played for the New York Yankees, Arizona Diamondbacks, Tampa Bay Rays, the Marlins, and the Dodgers. His best season statistically came in 2011 with the Marlins, when Choate struck out 31 in just more than 24 innings with a 1.82 ERA.