Recent allegations against the American Humane Association's Film & TV unit have renewed concerns about the unit's effectiveness, and have potentially vindicated PETA's previous alarm-ringing, which the animal rights group says were ignored.

Last week, a former employee of the AHA’s Film & TV unit filed a wrongful termination suit against HBO and the AHA, claiming that she was fired as director of production after pressuring her colleagues in the unit, which monitors the safety of animals actors used in Hollywood productions, to report what she claims was “systematic and unlawful animal abuse and cruelty” on the set of HBO’s horseracing drama “Luck,” which was cancelled in March after three horses used for the production were killed in separate, accidental incidents. A horse wrangler who worked on the series disputes her account, insisting that HBO and the AHA were committed to ensuring the animals’ safety.

The lawsuit and the circumstances leading up to it illustrate the ongoing cold war between the American Humane Association and People for the Ethical Treatment of Animals, or PETA, arguably the two best-known animal rights groups in the United States. Though PETA has nothing directly to do with the lawsuit, a spokesperson said it vindicates PETA’s aggressive, and largely futile, attempts to convince HBO that horses were in grave danger on the set -- warnings that PETA issued prior to the start of the series’ filming and again after receiving numerous reports of concerns about the horses’ safety.

“There were a number of accusations that we did not have the facts straight,” Kathy Guillermo, PETA’s vice president of laboratory investigations, said. She was alerted to the alleged safety violations by anonymous whistleblowers who witnessed reportedly dangerous conditions at the Santa Anita racetrack, where the racing sequences were filmed. Guillermo said she had no way of knowing if the lawsuit’s plaintiff, Barbara Casey, was one of the people who contacted PETA anonymously while the series was in production. “I was getting frantic whistleblower calls,” Guillermo said. In March, she sent an email to HBO, which IBTimes obtained, urging them to revise safety protocols. Almost a year later, HBO has still not responded. “They at the very least buried their heads in the sand, if not more,” Guillermo said.

PETA has long questioned the ability of AHA safety officers to enforce animal safety guidelines during production, as the AHA has authority over the care and treatment of animal actors only during active filming. Additionally, the Film & TV unit is partially funded by grants from SAG and AFTRA, which invites accusations of a potential conflict of interest.

Representatives for HBO and AHA were not eager to address specifics of the “Luck” lawsuit. An HBO rep declined to comment further than the company’s official statement, which insists that the production met all safety guidelines and advises anyone with questions about Casey’s employment to contact the AHA. The AHA representative said the organization is “unable to comment on pending legislation.”

The “Luck” horse deaths were not the first time the AHA has faced uncomfortable questions about its ability to ensure the safety of animals used in film and television productions. In 2005, two horses died on the set of “Flicka,” a 20th Century Fox feature film. Though the AHA maintained that the deaths were “unpreventable” and that the filmmakers and animal handlers complied with AHA’s safety guidelines, the group did not give “Flicka” its trademark “No Animals Were Harmed” disclaimer. A man who claims to have worked as an extra on “Flicka” organized a “Boycott Flicka” campaign in response to what he said was animal cruelty on the set of the movie. He also claims that 20th Century Fox offered him $2,500 to “keep quiet” about what he allegedly witnessed and accused AHA of protecting the studio. (IBTimes was unable to immediately verify the legitimacy of his claims.)

Four years earlier, the Los Angeles Times ran a feature questioning the policies of AHA’s Film & TV Unit, accusing the then-“little-known” unit of being “slow to criticize cases of animal mistreatment, yet quick to defend the big-budget studios it is supposed to police.” The L.A. Times claimed in the article that the AHA filed a lawsuit attempting to block its publication on the grounds that it might include information from a confidential document drawn up by AHA lawyers. (The motion was denied.)

Aside from the potential conflict of interest posed by funding sources, the Film & TV unit’s effectiveness is undermined by limits on its jurisdiction -- something that the AHA says it aims to expand. Still, these limits work to curb AHA’s accountability in cases where animal mistreatment, injury and death occur outside of active filming -- as was the case with “The Hobbit,” which filmed in New Zealand. Several animals, including two horses, were killed in 2011 due to hazardous conditions at the facility where the animal actors were housed, a significant distance away from the set, and beyond the authority of the AHA. In direct response to reports of “The Hobbit” animal deaths, AHA announced it would be seeking additional funding in order to expand its oversight. (“The Hobbit” was given a “Special Circumstances” safety rating.)

In Sept. 2012, PETA sent a letter to the AHA, calling for increased monitoring of animal safety and revision of the safety ratings given to film and television productions where there were reports of animal mistreatment, injury and death. The letter cited incidents (not all of them resulting in injury or death) during the filming of “The Hobbit,” “There Will be Blood” and HBO’s “Boardwalk Empire,” among others. The AHA “strongly refuted” PETA’s claims as coming from “second- and third-party sources, including a disgruntled AHA employee. These allegations derive from falsehoods, inaccuracies and deliberately misleading statements.” While the AHA did not respond specifically to each item in the letter, it insisted that the horse death on the set of “Boardwalk Empire” was the result of natural causes, not the stress of filming, as the 21-year-old horse was not required to perform any action.

Matthew Chew, a veteran horse wrangler who worked on “Luck,” insisted that HBO and AHA were not in any way culpable for the accidental horse deaths on the set. “HBO went out of their way to provide the best possible environment,” Chew said. “We had some rotten luck.” Chew said that a minimum of three AHA reps and two licensed veterinarians were always present during filming and that animal wranglers “were micromanaged by the AHA in every aspect of our care and our procedures.”

Chew described Carey as a casual friend and seemed somewhat surprised by her allegations. “In my dealings with her, she was really fair, and she treated us well,” he said, adding, “It appeared that the AHA has dysfunction in its own internal political structure.” Still, he did not feel that any internal dysfunction compromised the safety of the animals on the set. “The horses were taken care of as well as any horses could be,” he said. “Still, we weren’t happy with the outcome.”

When asked why the whistleblowers PETA described may have reported unsafe conditions on the set, Chew blamed a lack of familiarity. The whistleblowers “don’t know what they are looking at,” Chew said, referring specifically to one sequence that could have appeared as though a horse was being whipped. The “whip” used in that scene was made of foam, he explained, and the riders on set made the whipping sound with their boots. “I think it’s a misinterpretation through ignorance,” he said.

Guillermo said that PETA is not equipped to monitor the safety of animal actors itself, nor is the group seeking any direct influence over safety monitoring on film and television sets. PETA’s official position is that live animals should not be used in productions at all, advocating instead for the use of CGI to create scenes using animal characters.

Guillermo is optimistic that Casey’s lawsuit may result in stricter enforcement of animal safety.

“This lawsuit shows that the days when animals could be abused and killed behind the closed doors of the film and television industry are over,” she said. “If you harm an animal in Hollywood, PETA is going to find out.”