James Frederick Lilja was the drummer of the punk rock band The Offspring between 1984 and 1987.

While with the group, Lilja helped write the song "Beheaded". Dexter Holland has said "He wanted to get into medical school so bad he really didn't come to the practices, so we let him go". Later after getting into medical school Lilja became a gynecologic oncologist. In medical school, he was drummer for the U. Pittsburgh Med School house-band, The Sons of Cecil (named after Cecil Jacobson, a man who impregnated multiple unwitting women, in his own fertility clinic, with his own genetic material). At night, the band switched instruments, donned clown suits and clown makeup, and played as the punk rock band Clowns of Death.

Later, in residency, Lilja headlined the cover band Tastes Like Chicken, composed of doctors from several Houston hospitals. The band was locally famous for never having a demo, never playing a single original song, and never seeking air play-- yet consistently attracting large crowds through the various hospital departments for which the band members worked. Later, in the group Fellowship, Lilja delved into A-D recording with computers while still playing drums.

Currently, Lilja is a full time surgeon working in San Jose, California, where he presently plays with the band Happy Accident.