From Halopedia, the Halo wiki
In 2542, he gave up the job because he felt he was getting too old and became an anthropology professor at a college in Boston, Massachusetts. He recognized one of his students, Rani Sobeck as having detective-like qualities, and decided she would make a good ONI agent. He contacted his old colleague Colonel Herzog to suggest that he use Rani as a spy at Chawla Base, and Herzog later agreed with his proposal.
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