She first came to notice when she was cast as Jenny Wilder in Little House on the Prairie, which she followed up with roles in films such as Heathers. She was then cast as the oldest Witherspoon sibling, Kris, on the family drama Our House, which ran from 1986 to 1988.
She starred on the Aaron Spelling-produced Beverly Hills 90210 for four years, from 1990 to 1994. Although her departure from the series was reportedly acrimonious, it didn't stop Spelling from casting her in another series, Charmed. She left that series in 2001, after three years, claiming that her best work was being wasted on a show "for 12-year olds" (though rumors persist that her departure was against her will, due to a feud with costar Alyssa Milano). She hosted Scare Tactics on the Sci Fi channel until the 2004 season. She was a former regular on the failed TV series North Shore, a return to her prime-time soap roots.
Her private life has also been turbulent, with a six month marriage to Ashley Hamilton, son of George Hamilton.Doherty posed for a nine page pictorial in the December 2003 issue of Playboy magazine. She had previously appeared in the March 1994 issue.
In 2005, she was cast in the new TV comedy Love Inc. but was dropped from the show just months before the debut in fall.It has been noted that her left and right eye are not horizontally aligned.She is a Southern Baptist and a Republican.