HBO and Stewart Productions, the producer of the ill-fated horse racing drama series "Luck," are seeking to distance themselves from a lawsuit filed by a former American Humane Association employee.

The Hollywood Reporter’s Hollywood, Esq., reports that an amended filing in the case, from former AHA Director of Production Barbara Casey, alleges animal abuse is rampant in Hollywood and accuses the AHA of "kowtowing" to Hollywood producers — especially HBO.

Casey was fired by AHA after she complained about alleged mistreatment of horses during production of "Luck," on which three horses reportedly died. She has filed a wrongful termination lawsuit against AHA, and is fighting to have HBO and Stewart Productions included in the suit.

"In an amended complaint that alleges that the entertainment companies are liable for ‘aiding and abetting a wrongful termination,’ she claims that the AHA ‘kowtows’ to Hollywood producers," THR reports. "Her legal papers included graphic pictures and discussed how her former employer looked the other way or covered up animal abuse on such productions as ‘The Life of Pi,’ ‘War Horse’ and ‘The Hobbit.’"

The report adds: "Casey reserved special scorn for AHA’s relationship with HBO, and now the cable network has struck back with a motion to strike her lawsuit."

HBO and Stewart are invoking the First Amendment in their argument against what they reportedly see as a frivolous lawsuit, the story notes.

The article quotes their argument in part: "The alleged acts by HBO and Stewart that form the basis of plaintiff’s claims against them were unquestionably in furtherance of defendants’ right of free speech because they were in aid of and incorporated into a broadcast in connection with a public issue."

"They add that horse-racing scenes were the ‘core of the program’s content’ and that ‘the animal actors in "Luck" were an essential element of both the drama and the excitement of "Luck" and they were fundamental to the series’ creativity,’" THR reports.

The judge handling the case has already indicated an inclination toward letting HBO and Stewart out of the case, the report notes.

"The AHA is also unhappy with Casey’s litigation," THR adds. "Upon the filing of her amended complaint, which made allegations like AHA’s president attending red carpet events with producers and celebrities, and AHA having conflicts that resulted in the ‘concealing (of) animal deaths and injuries as a matter of course,’ the organization made a public rebuke."

The report quotes a statement from the AHA saying: "We absolutely and categorically deny the sensationalist, inflammatory, misleading and untrue allegations in Ms. Casey’s amended complaint, and we look forward to vigorously defending ourselves through the proper legal channels."