The video begins with a warning: “Some viewers may find the following footage distressing.” Then there is the sound: the whoosh and crack of a whip.

It starts, and doesn’t stop. Team GB’s former dressage champion, Charlotte Dujardin – a three-time gold medallist – is shown in a riding hall, shadowing a horse and rider on foot as a third person films the scene. With a long whip, she strikes the animal upwards of 20 times in one minute.

The incident was filmed a few years ago, during a coaching session held by Dujardin in private stables, but footage was circulated last week alongside an official complaint.

Having been hailed as the “golden girl” of dressage and widely tipped for a damehood, Dujardin has been banned from the Paris Olympic Games amid public outcry and a pending investigation by the sport’s governing body, the International Federation for Equestrian Sports (FEI).

In a statement, Dujardin said she was “deeply ashamed” and “sincerely sorry”: “What happened was completely out of character and does not reflect how I train my horses or coach my pupils.” Dujardin’s fellow Olympic riders have condemned her methods, with Team GB’s Tom McEwen telling press: “We are here 110% behind horse welfare.”

But the scandal, plus more recent reports of alleged equine abuse at the Games, has provoked scepticism and renewed debate about the ethics of involving horses at all.

Days after Dujardin’s disgrace, the Austrian rider Max Kühner – ranked third in the world – was accused of equine abuse, having allegedly hit a horse’s legs with a bar in May 2023. (Kühner has said the allegations “have no basis whatsoever”; an investigation is pending.)

Brazilian rider Carlos Paro received an official warning for potentially causing “unnecessary discomfort” to his horse, after the FEI received photos of Paro apparently hyperflexing the animal’s neck, compromising its breathing, in a banned training move called “rollkur”.

Meanwhile, at the Paris Games, riders have already been eliminated from competition on welfare grounds. On Tuesday, the Olympic debut of the US team’s Marcus Orlob was terminated midway for blood on his horse’s leg, which he attributed to an accidental knock. Earlier, Italy’s Emiliano Portale was likewise excluded after his horse was found to be bleeding from the mouth post-competition.

Commenting on Portale, the FEI clarified that eliminations under this rule did “not imply any intention to hurt or harm”. But for Peta, the global animal rights organisation, that particular horse has bolted. Having worked to publicise the complaints about Kühner and Paro, it is now calling for equestrian sports to be removed from the Olympic Games entirely.

“We’re not talking about isolated events; there is a pattern of abuse,” says Jennifer White, Peta’s senior communications manager in the UK.

At the Tokyo Olympics in 2021, a Swiss horse had to be euthanised after tearing a ligament on the cross-country course. In the showjumping event, a gelding in the Irish team was shown competing with a visible nosebleed, potentially indicative of undue exertion.

Whether or not these examples register as animal abuse, or risks incurred in the pursuit of sporting excellence, may depend on your engagement with equestrian sport, and your own ethical lines.

For Peta, which takes the view that “animals are not ours”, any control, suffering or exploitation is unacceptable. “We know that whenever animals are treated as commodities and exploited for human gain, their best interests go out of the window,” says White.

It is particularly egregious in the case of the Olympic Games, she adds, intended as they are as a celebration of human athletic excellence. “At the end of the day, these horses don’t care about gold medals, they don’t choose to participate … There’s just no reason for it.”

The organisation has been emboldened by the removal of the horse event from modern pentathlon, after a German coach punched a horse during the Tokyo Games, causing outrage. That the sport’s governing body voted to replace horse riding with cycling, after 109 years, is proof that “change is possible”, says White.

In condemning Dujardin’s conduct, Olympic riders and representatives have rejected suggestions that it is in any way typical. “Your teammate is an animal in this sport and what we saw was inexcusable,” the US Olympic rider Boyd Martin told AP.

In the same interview, David O’Connor – who, having won gold at the 2000 Games, is now chief of the FEI’s eventing committee – denied that abuse was endemic. “We are trying to do everything we can to find out about unethical behaviour and put our foot down wherever it happens.”

But, within the broader equestrian world, the Dujardin video has sparked soul-searching, as well as shock.

“I found the whole thing really, really upsetting,” says Esther Fox, who has ridden horses all her life, worked as an equine veterinary nurse and trained as a steward. Until early this year, she also competed (though never professionally) in dressage, showjumping and cross-country.

Fox does not believe equestrian sports are inherently cruel, and stresses that she worked with many individuals and establishments who “really do train horses beautifully and brilliantly”. But, she says, the harsh methods displayed by Dujardin were not an “isolated incident”. “I think the reason it’s all so emotive for me is that I’ve literally been speaking out about this since I was 19.”

In her experience, “welfare was very poor” within the higher levels of dressage in particular. Fox says some horses were confined to stables nearly round the clock, and would show signs of whips and spurs.

Her concern about widespread neglect of horses’ mental and emotional welfare was partly what led her to leave the sport and retrain as a physiotherapist. Many feel the same way, Fox says, but don’t feel comfortable speaking out. “It’s such a close-knit world.”

April (not her real name), another former dressage rider, says she witnessed harsh treatment of horses during her time in the sport, decades ago, but says they reflected prevailing approaches at the time. “There was a common practice that if you met resistance in the horse that wasn’t physical, which seemed to be mental, you pushed through. Only then could you reward with softness.”

Since the revolution begun by “horse whisperer” Monty Roberts, humane training of sports horses increasingly eschews harsh treatment and tools in favour of positive reinforcement (like modern approaches to training pet dogs, versus outdated discipline). But old attitudes die hard, says April, particularly when money and medals are at stake. “I do think there are some aspects of dressage that need to change.”

At the top level in particular, there is evidence of a structural problem. Just this Wednesday, a Danish investigation published photographs of horses with apparent wounds and in potentially “extreme pain” at high-level dressage competitions. Though the Danish Equestrian Federation said the images were insufficient for investigation, three of the riders implicated (Nanna Skodborg Merrald, Nadja Aabo Sloth and Cathrine Laudrup-Dufour) are representing Denmark in Paris. A fourth, Carina Cassøe Krüth, had already withdrawn earlier this month after compromising footage surfaced from 2022. And yet another top Danish rider, Andreas Helgstrand, was excluded from consideration for the Olympic team after a TV exposé revealed rollkur and other bad practices at his prestigious stables.

Fuelling the debate are emotive and deep-seated questions about what, in these enlightened times, humans owe animals. Horses were domesticated about 3500BC, and have since been used for war, work, transportation, sport and companionship.

But while “there is a surfeit of information” on humans’ deep feeling for horses, as one 2021 study put it, “it remains elusive for us to truly know what a horse thinks or feels” – not least about us.

“When horses are bonded with a human, I think in many cases they enjoy having that kind relationship,” says Susan Wagner, the founder of Equine Advocates, a New York-based organisation that rescues horses (mostly from the meat trade) and educates about equine abuse.

But coercion, cruelty and abuse are rife among all working animals used to produce profit, Wagner says; the Olympics are just more visible, and higher stakes. “Whenever there’s a lot of money or glory involved, people do things to animals because they want them to perform a certain way.”

Outside of the Olympics, mainstream attention focuses on horse racing (a separate discipline to the specific equestrian sports of dressage, showjumping and cross-country). Since 2007, the website Race Horse Death Watch has recorded 2,854 deaths at British racecourses; many more will have suffered injury and had shorter lives. But it’s not just equestrian sports: Peta has condemned horseback riding as unnatural, and a “decision made solely by one individual with little benefit to and no input from the other”.

Various studies have suggested that carrying larger riders in particular may harm horses, inducing temporary lameness or apparent pain. But the risk is said to be mitigated by an appropriate match of horse and rider, a well-fitted saddle and proper riding technique. A 2023 study acknowledged “debate as to the amount of weight a horse should be expected to carry”, but said there was general consensus that horses did not show signs of stress until “rider/horse body weight ratio” exceeded 20-25%.

Wagner enjoys riding horses and even mules for fun, but adds that some commonly used kit can take a severe toll. Double bridles, curb bits, side reins and nosebands are used to exert greater control over horses, even at the Olympic level: another topic of controversy.

Kay Willoughby, a registered equine behavioural consultant based in Northampton, says best practice centres the relationship between horse and rider: “A horse has got a mind of its own.”

Willoughby competed in equestrian events for 20 years, and now works one-to-one with clients to train horses and tackle behavioural problems. She says Peta’s criticism of the sports as necessitating “violence and coercion” can overlook the humane training that horses undergo to be competition-ready, and the connection forged with their rider.

“There are people out there that do show-jumping or cross-country bridleless – it is possible,” she says. Equally, when Willoughby uses a lunge whip (the same kind used by Dujardin) to direct a horse, she doesn’t make contact.

In her work, Willoughby centres positive reinforcement and tailors her approach to each horse’s individual temperament. “I don’t have any preconceived ideas about what they’re going to do, because you don’t know. You introduce them to various things, and you see this is what they enjoy, and this is what they’re good at,” she says.

Not every horse is a born athlete, or suited to competition, says Willoughby – just as not every rider will make it to the Olympics. But the pairings that do often have a strong bond. “It is completely a partnership.”

Willoughby points to Team GB’s Laura Collett, who just set an Olympic record score for dressage (a decade after almost dying in a fall at the 2013 Games) with her horse London 52, and Germany’s Michael Jung with his, named Chipmunk. “Those horses looked amazing; they absolutely danced for them.”

In some of the showjumping events, too, she saw only athletes performing at peak condition. “They were galloping freely, their ears were pricked, they didn’t look over tired … They looked as if they were enjoying themselves.”

But that is not always the case. At the Tokyo Games, Willoughby says she saw horses showing signs of fatigue that “in my opinion, would have been better pulled up”. Dressage in particular, as “one of the hardest things for a horse to do”, is taxing not only on horses’ bodies, but on their minds.

Often, she says, she sees animals competing with visible tension. That’s not necessarily to be equated with abuse – “they are obviously performing in a stressful situation, and a strange environment” – but it’s nevertheless “not ideal”, says Willoughby. “I think the horse’s emotional state is often overlooked.”

Though there are rules and safeguards in place at the Olympics to protect horses’ wellbeing, including routine vet checks, they are not necessarily failsafe or comprehensively enforced. This Paris Games is the first to have an equine welfare coordinator on site, itself indicative of animal athletes’ lower priority.

Paul McGreevy, a professor at the University of Sydney’s School of Veterinary Science, and an expert in horse behaviour and welfare, notes that technology exists to accurately measure the tightness of nose bands; tissue damage from whips, spurs and bits; and even the lightness of rein cues. It’s just not used at the Olympics.

“If the technology is good enough to maintain rule-keeping and integrity in elite soccer and cricket, it should be good enough to ensure horse welfare and eliminate subjectivity in the judging of equestrian sports,” McGreevy says.

Willoughby supports greater penalties, to discourage bad actors and demonstrate to “non-horsey people” that the sport is taking welfare seriously. But she doesn’t see the point of banning equestrian events from the Olympics when riders compete all year round. At shows, she says, she has challenged bad practice “and watched 20 other people not [do anything]”.

What’s needed is a culture change, Willoughby says – starting “at the bottom” with the next generation of equestrian sportspeople. The filming and sharing of footage, as with Dujardin, might help to expose bad practice, she suggests. “I’d be happy to have cameras all around my yard, on 24/7.”

But until horses’ welfare can be guaranteed, for some, the promise of Olympic glory isn’t worth the cost of entry. Wagner, of Equine Advocates, points out that the recent abuse allegations are “nothing new” for the Games, “and it’s happening in front of the entire world”.

• This article was amended on 8 August 2024 to add the number of deaths recorded at British racecourses since 2007 by Race Horse Death Watch.