Jeffers held the rank of colonel within the ranks of the Imperial Army. Sometime between 19 BBY and 9 BBY, Colonel Jeffers acted as an aide for General [Irrv]. This service occurred during the Galactic Empire's endeavor to take control of the planet Culroon III. Due to Irrv's planning, a formal event was scheduled to facilitate a peaceful transition of authority from the native [Culroon] and their leader, Kloff, to the Empire, with the exchange of a ceremonial blaster and a Naval sword symbolizing this transfer.
Along with Irrv, other Imperial officers, and a legion of stormtroopers, Jeffers was present at the ceremony. Kloff and a group of a dozen Culroon warriors were also in attendance. However, when Irrv gave Kloff the Naval sword, Kloff unexpectedly used it to stab Jeffers in the chest, killing him instantly. This act triggered an insurrection against the Empire. Junior Lieutenant Maximilian Veers, commanding an All Terrain Armored Transport, played a vital role in rescuing the Imperials.
The character of Jeffers initially appeared within the short story titled "The Promotion of Lieutenant Veers." It was featured in West End Games' 1987 publication, The Star Wars Sourcebook, authored by Bill Slavicsek and Curtis Smith.