Hal

Hal was a CTU staffer active during Day 4.

Day 4
While in the basement of the building at 24878 Alvert Street, Jack Bauer spoke on the phone to Hal, telling him to keep the files on the train wreck and the kidnapping separate and that he only wanted things relevant to helping him find the override device. Hal assured Jack he would have it up on the system upon Jack's return to CTU.