Producer of 'A Dog's Purpose' Explains What Happened on Set

— -- Gavin Polone, a producer of "A Dog's Purpose," has spoken out about the now infamous video taken on the film's set that showed a dog apparently being pushed into turbulent water against its will.

Polone, who is also a columnist for The Hollywood Reporter, wrote an essay for the publication, condemning the incident and explaining the context in which it took place.

Although he was not on set the day the German shepherd named Hercules was seemingly forced into the water, Polone wrote that he found the incident "absolutely inexcusable."

"The dog trainer should have stopped trying to get the dog to go in the water as soon as the dog seemed uncomfortable, and the trainers should have had support under the dog as soon as he came to the side of the pool and/or had less turbulence in the water so he never would have gone under," Polone wrote. "The American Humane Association (AHA) representative who is paid by the production to 'ensure the safety and humane treatment of animal actors,' as its website states, should have also intervened immediately on both of those parts of the filming. So should have whomever was running the set. Those individuals should be held accountable and never used again by that studio or its affiliates."

TMZ released the video last week — which led animal rights group PETA to call for a boycott of the film.

Amblin Entertainment, who produced the film, and Universal Pictures, the film's distributor, told ABC News in a statement that the recording was being reviewed. According to Amblin, Hercules is "happy and healthy."

Polone said Hercules was "desperate" to jump into the water and had to be restrained by his trainer from going in before the scene was shot.

"The dog did the scene in rehearsal without problem, though it was from the left side of the pool, not the right side, which is where the dog is in the TMZ video. Also, in the rehearsal footage, it’s clear that there is a safety diver and a trainer in the pool to protect the dog in case of a problem, as well as two trainers, a stunt coordinator and a safety officer on the deck and that there are platforms built into the pool where the dog can swim to and stand, if need be," he wrote, adding that the water was 80 to 85 degrees. "Before the first real take, the handlers were asked to change the start point of the dog from the left side, where he had rehearsed, to the right side. That, evidentially [sic], is what caused him to be spooked."

Polone added that when Hercules balked at jumping in from his new position, filming was cut, "though not soon enough." Ultimately, the crew returned to the original shooting setup.

"The dog was comfortable and went in on his own, and they shot the scene," he wrote. "The TMZ video only shows the unfinished take of when the dog was on the right side. What is clear from viewing all the footage was that the dog was never forced into the water."

Polone also questioned PETA's call for a boycott.

"PETA says the film should be boycotted and no dogs ever be used in movies or TV. I would ask that if a teacher were to hit a student in class, should the whole school be closed and all the children left without an education?" he wrote. "This is a movie that is intended to reinforce the idea that animals are sentient and we should love and protect them, just like the movies and TV shows I saw as a kid made me understand."

Lisa Lange, a senior vice president at PETA, responded to Polone in an email statement provided to ABC News.

"It doesn't matter whether there was a diver in the pool to rescue the dog when he went under. It's irrelevant that he's now reportedly safe. What matters is that, according even to Polone, this dog made his feelings known, loud and clear, about being forced into rushing water to produce a swimming scene and attempted to escape — yet into the water he was made to go," the statement said.

"The fact that a producer like Polone — someone who genuinely cares about animals — failed to prevent cruel training techniques, failed to ensure that animals aren't living in squalor and failed to stop a dog from being terrorized during shooting exemplifies just how deeply entrenched the problems are in this business."