Karter was born in Harris County, Texas and raised in Saint Joseph, Missouri and Ridgway, Pennsylvania.
Karter began erotic dancing while in Missouri and was named the state's Déjà Vu Showgirl of the Year in 2007. She later moved to California to pursue an acting and singing career. Karter fell out with her manager when he discovered she had been working as an exotic dancer. While continuing to dance in California, she eventually moved into modeling and, after signing with the agency LA Direct Models, posed for shoots with erotic photographer Holly Randall.
Karter entered the adult film industry in September 2008. Her first scene was with Johnny Sins for Naughty America. In regard to her stage name, Karter has stated that Kagney was her real first name (her father named her after James Cagney) and Linn was her real middle name.[citation needed] She chose Karter as her surname because it "just fit perfectly."
In 2012, Kagney took part in Louis Theroux's Twilight of the Porn Stars, a BBC documentary about the porn industry, its struggling to compete with free internet alternatives, and the lives of famous porn stars.

