Jeffrey, a former Street Mary"s junior, started his VFL career at Geelong and with the exception of one night match spent all of his time in the reserves. A serious knee injury looked to have ended his league career and he left Victoria, only to be called up by Street Kilda to play a game in 1987. After playing 14 games for Street Kilda in 1988, Jeffrey again left the state, spending the 1989 season in New South Wales with Jerilderie.
He was re-signed by Street Kilda in the 1990 preseason draft, with the 23rd draft pick.
Used mostly as a defender, Jeffrey had his best season in 1990, not missing a single game and averaging just under 16 disposals. Although he had represented the Northern Territory in the 1988 Adelaide Bicentennial Carnival, he played State of Origin football for Victoria in 1990.
At the end of the 1991 season, Jeffrey was traded to the Brisbane Bears and on debut became the 100th football player to play for the club He coached Wanderers until 1997, during which time he was also coach of the territory"s Teal Cup side and the league"s representative team
Joining Palmerston as playing coach in 1998, he steered the club to four consecutive grand finals.
He coached their 2000/01 and 2001/02 premiership sides. Jeffrey is an Indigenous Australian and represented the Indigenous All-Stars in 1994. On 17 February 2012 the Northern Territory News reported that Jeffrey will be the Labor candidate for the seat of Brennan in the 2012 Northwest Territories election.