Shields has not participated in the Packers' voluntary practice sessions this offseason. Green Bay begins its mandatory minicamp Tuesday.
Last season, Shields intercepted three passes during the regular season and two more in the playoffs, including one he returned 52 yards for a touchdown against the San Francisco 49ers.
A shin injury forced him from six games, however, and he played on only 53.9 percent of the Packers' defensive snaps.
Information from ESPN.com NFC North blogger Kevin Seifert was used in this report.