PETA has been known for their dramatics, and I personally do not agree with a lot of their actions. However, the wranglers who cared for said animals where the ones who brought this situation to light. They are the ones who said the production co. was responsible. The American Humane Ass. oversaw only the filming, not the facilities where the animals were kept. The wranglers expressed concerns to their supervisors, and the production co- Warner Bro.
The buck stops at the one who produced this film, who chose the facility site and ignore repeated concerns. If you produce a film you take responsibility for your actors as well as any animals involved. One can delegate to others, but in the end they are responsible.
One death, one injury was too much. Situation was brought to light and ignored.
This is true. Part of being in charge is, well, being in charge.