"We are all well aware that your ongoing all night heavy partying is the real reason for your 'exhaustion.' We refuse to accept bogus excuses for your behavior," wrote Robinson.
He threatened to hold her "personably accountable" for actions the Morgan Creek chief said had "resulted in hundreds of thousands of dollars in damages."
"Lindsay Lohan has not signed on to any studio films in a while," Siegel said, "and I don't think that is a coincidence."
Downey's battles with drugs and the legal system for two decades dimmed a brilliant career hinted at by stellar performances in "Less Than Zero" and "Chaplin," for which he received an Oscar nomination.
"For years he was not making any studio movies. He was making independents," Siegel said. "He has just started to land high-profile roles."
Downey has received critical acclaim for his role in the recently released "Zodiac," and he will star as a superhero in the big budget action drama "Iron Man," scheduled to begin filming this month.
Young people take their cues from popular culture and from celebrities.
Marketers rely on that dynamic. So it is troubling for some to note that the headlines made by entertainers in the throws of addiction have an eerie echo in a startling new report about college kids.
Almost half of all full-time college students (4.8 million) binge drink and/or abuse prescription and illegal drugs, according to the National Center on Addiction and Substance Abuse at Columbia University.
The comprehensive study also found that more than one-third of the students did not seek help because they feared the social stigma attached to substance abuse.
With more and more celebrities turning to treatment and admitting they have a problem, perhaps there is a message really worth marketing to young people.