According to biographies of Elizabeth Taylor, she was a regular cannabis consumer in the 1970s:
(Tokin Women) Liz’ experimentation with marijuana began in mid-1973, when she partied with Peter Lawford and his son Christopher, hitting hot spots like Candy Store in Beverly Hills. Peter’s friend Arthur Natoli recalled, “[Lawford] and Elizabeth used to turn on together. They were high on pot a lot. I don’t know if he supplied her.” (p. 222)
Taylor was 19 when she was cast in A Day in the Sun opposite Montgomery Clift, and she had a lifelong devotion to Clift, who smoked marijuana (as did James Dean). According to Amburn, “Elizabeth sometimes ditched [second husband Michael] Wilding to slip off to Oscar Levant’s Beverly Hills house with Monty, where the pianist serenated them with Gershwin tunes as they whiled away afternoons and early evenings.”
Her fourth husband Eddie Fisher was revealed to be a pot smoker by his daughter Carrie in her 2008 book Wishful Drinking. In his 2008 autobiography, Tony Curtis says marijuana was very popular in Hollywood around the time of his 1971 bust for carrying pot through Heathrow airport.