Last Samurai LawsuitUPDATE: It’s like a scene from a John Grisham movie: $800-per-hour attorneys for O’Melveny & Myers in posh Century City law offices trash-picking for used soda cans, torn candy wrappers, and dirty paper napkins. But this is a real-life legal case about the 2003 movie The Last Samurai that’s heating up. A federal court judge will hear oral arguments in the case on Monday. The reason for the rubbish rooting is clear: according to Warner Bros’ filings, “as much as $100 million in potential liability” is at stake here about the film that reportedly made $700M from theatrical grosses and DVDs. The proceedings began in 2005 when brother screenwriters Aaron and Matthew Benay filed suit in federal court against the studio Warner Bros and the film’s director Ed Zwick, writer Marshall Herskovitz and John Logan, the Zwick-Herskovitz production company Bedford Falls for breach of implied contract. The Benays contend that their copyrighted script The Last Samurai became the film The Last Samurai with the same fictional character and premise, and, surprisingly, the same title. In 2010, the U.S. Ninth Circuit Court ruled that the “similarities are substantial for purposes of an implied-in-fact contract under California law”. The case is set for trial on March 20th.

In the course of discovery, an anonymous source produced documents incriminating to Warner Bros. So the studio put high-profile O’Melveny & Myers partner Daniel Petrocelli on the case. To clear themselves as the anonymous source of the documents incriminating to Warner Bros, the Benays submitted to DNA testing. But that wasn’t enough for Petrocelli et al. According to court filings, O’Melveny attorneys flouted court instructions and clandestinely obtained additional DNA from the plaintiffs as well as from their attorneys.They used the occasion of a deposition inside the O’Melveny offices at 1999 Avenue Of The Stars to collect used napkins, coffee creamers, a Twix wrapper, and Diet Coke and Dr Pepper cans from the Benays and their counsel deposited in the law office’s trashcan.

Super-lawyer John Marder of Marder Zink & Karlzen was understandably outraged as plaintiff for the Benays and has asked the court for sanctions including imprisonment and fines as high as $250,000 per violation. In a declaration, Marder said, “In my 30 years of practice, I have never had opposing counsel violate my privacy to this degree.”

I find it shocking that Warner Bros would hire a lawyer to debase the studio like this. Interestingly, this is not Petrocelli’s first brush with so-called “dumpster diving”. In 2004, the attorney castigated Winnie the Pooh licensing heirs for rooting around in Disney’s garbage for evidence in their royalties dispute with the studio, and the litigator used that accusation to get the case thrown out. Now Petrocelli finds himself on the other side of the trash bin.

So for all the legal machinations, what were the results of the DNA analysis? Ironically, nothing. The O’Melveny DNA report (see documents here and here) found that as many as 3 in 5 American males could have sent the documents — or any of 91 million people, according to the 2010 US Census. Petrocelli’s argument back is that those long odds don’t matter because the Benays can’t be ruled out.

Aaron and Matthew have written scripts for notable Hollywood figures such as Leonardo DiCaprio, Ridley Scott, and Brian Grazer. They penned the upcoming San Francisco earthquake epic 1906 which Brad Bird is directing based on the novel and screenplay by James Dalessandro.

Editor-in-Chief Nikki Finke - tip her here.

For all of Deadline's headlines, follow us @Deadline on Twitter.