Buckel was a senior counsel and marriage project director at Lambda Legal, the American organization that focuses on lesbian, gay, bisexual, and transgender (LGBT) communities.
In 1996, Buckel represented Jamie Nabozny in Nabozny v. Podlesny, a case heard in the United States Court of Appeals for the Seventh Circuit regarding the protection Nabozny did not receive while at school. Buckel represented Nabozny in his claims stemming from "consistent and significant anti-gay bullying and abuse."
In 2000, Buckel was the lead lawyer for the estate of Brandon Teena, a transgender man who was raped and murdered in Nebraska, when Teena's family recovered damages against negligent law enforcement officers. Buckel stated, "It's a very important case, not only within Nebraska but nationally." The story inspired the 1999 biographical film Boys Don't Cry.
In 2006, Buckel argued before the Supreme Court of New Jersey in Lewis v. Harris that "for the government to use the label 'civil union' is a considered choice of language that assigns us a second-class status."
Fox News called Buckel "a pioneering lawyer for gay and transgender rights." In a statement to the Huffington Post, Camilla Taylor, senior staff attorney for Lambda Legal, stated, "His thoughtful and engaging advocacy broke through many stubborn misconceptions and showed it was possible and necessary for our movement to speak up for bullied, ostracized LGBT young people." Susan Sommer, a former attorney for Lambda Legal, called Buckel "one of the architects of the freedom to marry and marriage equality movement."
At the time of his death, Buckel was senior organics recovery coordinator with the NYC Compost Project. He previously was a volunteer coordinator of Added Value Red Hook Community Farm, where he practiced composting. He was nominated for a Solid Waste Association of North America Unsung Hero Award for his work in composting and for the environment.
Buckel wrote Guidelines for Urban Community Composting, a guide for composting in urban areas.