The Bears signed Boyle to their active roster from Detroit's practice squad Wednesday ahead of Sunday's game versus Green Bay, Jason Lieser of the Chicago Sun-Times reports.
With both Justin Fields (shoulder) and Trevor Siemian (oblique) listed as questionable for Week 13, Chicago saw fit to add Boyle as a short-term insurance policy. There's a shot Boyle could be thrust into a starting role immediately, but as long as one of the aforementioned signal callers is available Sunday, Boyle should fill a reserve role.