Just hours after Deniz, a beautiful brown-and-white carriage horse, collapsed and died in Central Park June 9, the activists pounced.

Edita Birnkrant, executive director of the anti-carriage group NYCLASS, posted a video of Deniz in his final moments, lying on the carriage drive.

“They’re f—ing abusers,” a male narrator says.

 “He doesn’t care,” the observer declares of the carriage driver.

The video ends with a blaring political headline: “Pass Ryder’s Law Before Another Horse Is Killed.”

That’s the City Council bill, long pushed by NYCLASS, that would ban carriage rides in New York City — and force a largely immigrant workforce into unemployment.

Birnkrant, along with activist groups like PETA and City Council Members Christopher Marte, Frank Morano and others, immediately used Deniz’s sudden death to push a narrative portraying carriage drivers as cold-hearted animal abusers.

Their rush-to-judgment propaganda sparked a barrage of hate directed at New York’s carriage drivers, 95% of whom have come to the US from countries around the world: Ecuador, Mexico, Brazil, Turkey, Tajikistan, Italy, Ireland, Poland and many more.

“Kill that f—ing immigrant,” read one vitriolic post. 

“Who owns these horse and carriage business? Gypsies? Foreigners?” went another.

In the park, carriage drivers have been cursed and menaced.

One activist spat at a group of carriage-riding tourists from India, splattering one of them.

Even elected officials who voted against Ryder’s Law last year were targeted.

Manhattan Councilwoman Carmen De La Rosa received a string of frightening messages: “I hope you suffocate and die a slow death”; “So either she passes the ban or I pray to God to burn down their houses.”

Dr. Gabriel Cook, the respected veterinarian who cares for many of the horses, insisted on sending Deniz’s body to Cornell University for a necropsy conducted by its pathologists.

That’s standard in our industry — maintaining a high standard of care requires learning the cause of a sudden and unexplained death so we can avoid putting the animals in danger.

And we learned a lot: The Central Park Conservancy has planted toxic plants along the perimeter of park drives. 

The gross necropsy found a substantial amount of what appeared to be Japanese yew branches in Deniz’s mouth and stomach.

Yews, and Japanese yews in particular, are “highly toxic in horses” — and the amount found was “interpreted as enough to be lethal,” according to the pathologist’s report.

So Deniz didn’t die because he was mistreated.

He wasn’t abused.

He wasn’t overworked.

He was not “killed” as NYCLASS and others claimed or strongly insinuated.

He chomped on a plant while his driver paused to let passengers take some photos.

Some, including the Conservancy, want to blame the driver, citing a rule that horses aren’t allowed to eat the park’s plants.

That’s a reasonable rule, but it’s in place to prevent damage to the foliage — not to protect lives. 

The Conservancy never warned carriage drivers of these highly toxic plants that could kill a horse — or a dog or a child as well.

That’s managerial negligence that goes right to the Conservancy’s top. 

Central Park was built specifically for carriage horses.

When Frederick Law Olmstead and Calvert Vaux designed it in the 1880s, they meant for it to be enjoyed in part by taking leisurely carriage rides through the sculpted landscape.

Horses have been there since day one.

Today, NYPD mounted police horses, Parks Department horses and recreational riding horses also use the drives.

It’s time to reject the hateful propaganda, and turn away from advocates whose politicized views aren’t supported by science or medical analysis.

It does no harm to 1,600-pound horses — bred over centuries for hard labor — if they give a few carriage rides a day in Central Park.

Instead of banning this vital piece of New York City history, council members and the public should instead support Intro 937, a horse welfare and job protection act introduced last week by Councilman Jim Gennaro.

This bill would implement immediate commonsense reforms — like installing hitching posts to safeguard horses from straying, more rigorous testing of carriage-driver applicants, improving the city’s temperature-monitoring system so carriage service can be halted more quickly on hot days, and more. 

As in any industry, accidents do happen — such as on Wednesday, when a carriage passenger was seriously injured.

But safety reforms like those in Intro 937 can address such incidents and help prevent them from occurring again. 

We, as a city, can work together to advance the welfare of our carriage horses, while also protecting the jobs that sustain immigrant families who came here to pursue their American dream. 

John Samuelsen is president of the Transport Workers Union of America.