Bulger testified the FBI didn't ask him about his fugitive brother for eight years.
Burton accused Bulger of exhibiting "selective memory loss" during his June 19 testimony on Capitol Hill despite receiving a grant of immunity.
"When FBI agents come to your office to talk about something, everyone's antenna goes up," Burton told the Boston Herald. The congressman said he recalls each time a federal agent has come to his office.
"For him to come before the committee and say he didn't remember something like that questions credulity," Burton said.
Bulger attorney Thomas R. Kiley said the UMass leader told the truth based on his memory.