From Halopedia, the Halo wiki
Silas Mogensen was a human who listened to Benjamin Giraud's Hunt the Truth audio journal in 2558. After Giraud's claimed the UNSC was spreading a false account of the Master Chief's backstory, Mogensen mailed Giraud an audio email where he expressed his enthusiastic support of Hunt the Truth. He praised Giraud as a "crusader" for the truth, and urged him to keep going and take the Office of Naval Intelligence off guard.
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