The character George, the biker boyfriend played by Aaron Eckhart, was based on Erin Brockovich-Ellis's Mexican-American biker boyfriend Jorge. Erin and Jorge did break up, but he did not leave her life. He was hired as a full time live-in nanny for Erin's children for several years, paid for by the law firm so that she would have more time to devote to her work.
Julia Roberts won the Academy Award for best actress for her role as Erin Brockovich and famously forgot to thank the real Erin Brockovich-Ellis in her acceptance speech. Afterward she was quoted as saying, "It doesn't bring out the Albert Einstein moment that you hoped it would."
Erin Brockovich-Ellis initially hoped Goldie Hawn would play her in the film, but Ed Masry - the real-life lawyer - thought that Roseanne Barr would be more suitable. Oddly enough, Masry actually stated once that Julia Roberts - who later won an Oscar for the role - would be the least suitable actress for the part, claiming that "..she has no tits and no foul mouth, so it wouldn't work." However, she was cast and Erin and the Academy were delighted with her work.
The real Erin Brockovich-Ellis actually got sick from the chromium poisoning she was investigating. Steven Soderbergh decided to leave that aspect out of the film as it would make Erin out to be too much of a martyr.
Hinkley's toxins made the real Brockovich sick at one point. Steven Soderbergh filmed a scene set at the hospital, but later cut it from the final product. "I didn't want people to think that this was going to turn into one of those movies where the protagonist gets terminally ill," he said on the DVD commentary. "It was a tough call, because Erin really did get sick and was hospitalized for a while."
The burgundy t-shirt with gold lettering she wears that is cut off says "Oakton Cougars". The costumers found this t-shirt in a thrift store and bought it, then researched online where this school may be. Once they learned that it is a high school in Vienna, Virginia, they contacted the school to ask if they could use the t-shirt in the film.
Together with his cinematographer Edward Lachman, Steven Soderbergh set out to shoot a major commercial film with an independent approach, filming it in a point-of-view manner. Shooting on location helped achieve a very naturalistic tone, and recruiting local extras from Hinkley who had been involved in the case added to the authenticity.
This is the last of Steven Soderbergh's films to be shot by a cinematographer other than himself, in this case, Edward Lachman. All of his subsequent films and TV productions have been shot by himself using the pseudonym Peter Andrews.
Albert Finney initially turned down the film. Danny DeVito had to convince Finney's girlfriend to convince the actor to change his mind, offering to schedule all of the actor's scenes as Ed Masry closer together so he wouldn't have to be in Los Angeles as long as earlier scheduled.