LOS ANGELES—Rosalie Ritz, a premier courtroom artist who for four decades chronicled dozens of high-drama trials, including those of Charles Manson, Patty Hearst and O.J. Simpson, died Friday. She was 84.

She died at her home in Walnut Creek in Northern California after a two-year battle with lung cancer, her daughter Sandy Ritz said.

Ritz’s work was seen on network TV and on AP wires, beginning with the infamous Army-McCarthy hearings in the 1950s. Soon after, she began drawing in courtrooms. Her trial illustrations are in a special collection at the Bancroft Library of the University of California at Berkeley.

An accomplished artist while still in her teens, Ritz began sketching live events when she was living in Washington, D.C., and got into a closed session of the House Un-American Activities Committee hearings. A CBS-TV producer offered to buy her sketches, and they were shown on the Edward R. Murrow news show.

Soon her services were in demand. When she moved with her family to California in 1966, settling in the San Francisco Bay Area, she became a freelance sketch artist with KPIX, a San Francisco CBS affiliate, and the AP, among others.

The AP brought her to Los Angeles for the trial of Robert F. Kennedy’s assassin, Sirhan Sirhan, in 1968, and she returned to the city for other trials. In 1996, the AP coaxed her out of retirement to draw the civil trial of O.J. Simpson, her last assignment.