Paul Morantz, the cult-fighting attorney and outspoken antagonist of Synanon, died in Santa Monica on Oct. 23. He was 77 years old. Mr. Morantz put himself in harm’s way to defend victims of the drug rehab program that ultimately morphed into a Marshall-based, self-styled religion with violent tendencies. He also became its most infamous victim.  

“He had a code,” his son Chaz Morantz told the Light. “When he saw people being taken advantage of by a cult leader, betraying the trust that their followers put in them, he didn’t feel like he could say no.”

After winning a $300,000 judgment against Synanon on behalf of a kidnapping victim, the drumbeat of threats against Mr. Morantz intensified. Charles Dederich, the cult’s leader, had exhorted followers to break his legs and Mr. Morantz had told the Light that he feared for his life. Synanon members had already assaulted a rancher neighbor and amassed an arsenal of weapons. 

Mr. Morantz himself had purchased a shotgun. He’d been checking underneath his car for bombs every time he drove anywhere, and he listened to make sure his border collies were barking before he entered his house. 

But on Oct. 10, 1978, after returning from a meeting with the attorney general to request more personal protection from Synanon, he didn’t think twice before reaching into his mailbox to grab what he thought might be a scarf or misshapen parcel. The moment he did, a rattlesnake sank its fangs into his hand. 

The snake—its rattle removed—had been placed there, he later learned, by two Synanon adherents: Lance Kenton, the 20-year-old son of bandleader Stan Kenton, and Joe Musico, a veteran and former addict. Their car was traced back to a Synanon property near Visalia, and the cult soon turned the men over to the police. 

Mr. Morantz was hospitalized for six days. Doctors told the press he nearly died, and the bite led to lasting nerve damage. He also felt the attack was the root of the ill health he suffered later in life, including possibly the rare form of bone cancer that ultimately led to his death. “That cancer could have been related to the snake bite, and my dad always felt like it probably was,” Chaz said, “but there’s no medical way to prove that.”

Synanon began as a heroin rehab program in a former beachside hotel in Santa Monica and eventually took up residence at what is now the Marconi Conference Center. Mr. Dederich, a former Alcoholics Anonymous member, decided that followers should never re-enter society, and he forced them to have abortions, undergo vasectomies, switch partners and commit violent crimes. After the rattlesnake incident, he was sentenced to probation and forced to give up control of the cult. Without his leadership, Synanon dissolved in 1991, and he died six years later.

Mr. Morantz lived long enough to see the death of Synanon in America and to fight a series of other cults and exploitative organizations in court. He represented victims of Scientology, EST, the Rajneesh movement and Jim Jones’s Peoples Temple, often pro bono. Many of those stories made it into his 2013 book, “Escape: My Lifelong War Against Cults.” But the rattlesnake on the cover reminded readers of the author’s most dangerous cult encounter.  

Mr. Morantz also lived long enough to witness a wave of renewed interest in Synanon—and to become one of its discontents. This summer, he sued the celebrity producers of “The Sunshine Place,” a podcast that told the Synanon story in the mold of wildly popular recent true crime series. Robert Downey, Jr., and his wife, Susan Downey, had stiffed Mr. Morantz, his suit in Los Angeles County court alleged, by using the contents of his 2015 book “From Miracle to Madness” without any deal or compensation. In an unusual turn, the ailing Mr. Morantz went so far as to accuse the Downeys of “elder abuse” based on the alleged copyright infringement and breach of contract. The podcast is narrated by Sari Crawford, the daughter of a Synanon leader, and features the voices of many former members. It tells Mr. Morantz’s story, but it does not use his voice. 

Chaz spoke regretfully of his father’s lawsuit. He said Mr. Morantz was “actively involved in finding the right people to tell his story in an authentic way, and really wanted to be a part of that.” That job now falls to Chaz, and there are at least two other high-profile projects on Synanon in the works: an HBO documentary directed by Rory Kennedy, and a multi-part docuseries that independent production company Pegalo Pictures sold to an unspecified major streaming network. 

Both productions contacted Dave Mitchell, the former editor and publisher of the Light who helped earn the newspaper a Pulitzer Prize in 1978 for its local coverage of the cult. With larger newspapers scared off by libel threats from Synanon’s lawyers, Mr. Mitchell felt he and Mr. Morantz were among the few who shared the mission of uncovering Synanon’s abuses. “He had a strong sense of purpose,” Mr. Mitchell said of the attorney. “I think we both felt we were on the same side exposing Synanon, so that created a kind of closeness.” 

“From Miracle to Madness” makes Mr. Morantz’s convictions clear. He saw violence and abuse by cult leaders as a betrayal of what should be a sacred bond between vulnerable people and their mentors, therapists, counselors and religious leaders. His work was never finished because that kind of exploitation had an insidious staying power. 

Synanon’s most infamous form of therapy, known as “the Game,” was a confrontational exercise in which participants were encouraged to verbally abuse each other, airing grievances, name-calling and making accusations that didn’t have to be true. In the final chapter of his book, Mr. Morantz explains that those techniques, designed to break down the will of addicts and lost souls, later made their way into other rehab businesses and, especially, boot camp-like tough love programs for troubled teens. At least one such program, a remote school called CEDU that became notorious for physical and emotional abuse, may have been named after Mr. Dederich. 

The Light interviewed Mr. Morantz in June about the continued use of Synanon’s methods in the troubled teen industry.

“When Synanon closed, I thought that was the end of it,” he said. But after reading the journalist Maia Szalavitz’s book “Help at Any Cost,” he discovered the extent to which the notorious and discredited cult he fought had given birth to an industry. “That’s when I found out that it wasn’t over,” he said. “People have been tortured and suffering worse than they ever did at Synanon.”

He saw the same kind of abuses at the highest levels of power. In an opinion piece last year, Mr. Morantz called Trumpism “America’s most dangerous cult.” When Donald Trump was elected, he wrote, “it felt like Charles Dederich won.” He knew extremist slogans and lies could drive people to commit violence the same way Synanon did. 

Mr. Morantz knew that promises of paradise by cult leaders and demagogues were empty. But he wasn’t a cynic. He understood the pull of these dreams. At the close of “From Miracle to Madness,” Mr. Morantz wrote about an emotional final visit to his former office, the headquarters of the litigation against Synanon. He cried thinking of the cult victims he had never been able to help. But most of all, he wrote, “I cried because I knew there would never be a Camelot, Shangri-La or Utopia.”