A prominent USA lawyer has died after setting himself on fire in a NY park in a protest against climate change.
Police pronounced Buckel dead at 6.30am.
He was the lead attorney in a lawsuit regarding transgender man Brandon Teena, who was murdered in Nebraska in 1993.
The New York Times said it received an emailed copy of Mr Buckel's note, in which he said: "Pollution ravages our planet, oozing inhabitability via air, soil, water and weather".
His suicide note expressed the hope that his death would serve as a call to action.
"Honorable goal in life invites honorable objective in death", he concluded.
Lambda Legal also highlighted key successes of Buckel's legal career, such as the unanimous ruling in 2009 by the Iowa Supreme Court allowing same-sex marriage - making the Midwest state only the third American state to recognize this right at the time of the decision.
Teena's story was the subject of the 1999 film Boys Don't Cry and Hilary Swank won an Oscar for her portrayal of him.
In a statement on Buckel's death, Lambda Legal described his death as "heartbreaking" and the attorney as a "beautiful human being".
He'd been doing the work for years - Buckel worked on Brandon v. County of Richardson - where the sheriff's office in 2001 was found liable for failing to protect Teena. "A lifetime of service may best be preserved by giving a life".
He was also the strategist behind same-sex marriage cases in New Jersey and Iowa, and helped set a precedent that U.S. schools have a duty to prevent anti-gay bullying.
In his note, Buckel compared his macabre demise with the suicides of those who set themselves afire to protest China's occupation of Tibet.
Buckel ran the NYC Composting Project out of Red Hook Community Farm.
Former colleague and lawyer Susan Sommer told the New York Times Mr Buckel was "all about justice, but he was also all about what it means to be human".
Adding, 'He was a very smart and methodical lawyer.
"My name is David Buckel and I just killed myself by fire as a protest suicide", read a hand-written message left at the scene.
Offered Camilla Taylor, Lamba Legal's director of constitutional litigation and acting legal director in a statement, 'This is a tragic loss for our Lambda Legal family and for the social justice movement'.