One of the investigators helped lead the inquiry into the homicide of Raymond Smoot, who died after he was savagely beaten at Baltimore's Central Booking and Intake Center.
The other investigator, who was based on the Eastern Shore, was involved in the investigation last year of state elections chief Linda H. Lamone.
Lamone kept her job.
"We feel (their reassignment) is strictly political," said Herbert Berry Jr., a labor representative for the Maryland Correctional Law Enforcement Union. "They have exceptional evaluations, no disciplinary history."
The department's secretary, Mary Ann Saar, authorized the transfer of the two investigators, Berry said, adding that the investigators fear that their transfers back into correctional institutions, where they have conducted investigations of inmates and staff, will put them in danger.