The attorney for Don Lewis, the 60-year-old millionaire and animal sanctuary owner who mysteriously vanished more than 20 years ago, believes his client might have been fatally strangled and tossed out of a plane over the Gulf of Mexico.
“I do have reason to believe he is dead,” attorney Joseph Fritz tells PEOPLE. “Too many indications of foul play, too many motives, too many opportunities. He wouldn’t leave him family, his fortune and his kids behind. There was enough motive and enough opportunity for something bad to have happened, and it probably did.”
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After Lewis’ Aug. 18, 1997, disappearance, deputies found his van abandoned at a nearby airport, where he had allegedly planned to take a trip to Costa Rica. Police found no signs of a struggle or blood inside — nor did they find proof that Lewis ever left the country.
In the intervening decades, his disappearance has remained a mystery. But since the release of Netflix’s seven-episode series Tiger King: Murder, Mayhem and Madness about the long-running rivalry between Joe Maldonado-Passage, aka “Joe Exotic,” the now-imprisoned big-cat enthusiast, and Carole Baskin, Lewis’ wife when he went missing, police are looking at the case again.
Fritz, who first spoke to Fox Nation host Nancy Grace, claims he heard from two sources that Lewis may have been lured to a nearby airport.
“We heard he got strangled with an electric cord in the backseat and was thrown out over the gulf,” Fritz alleges. “In my working theory, one person [was] flying the plane and one person [was] strangling.”
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“He was a pretty likable guy,” Fritz says. “He never really hurt anybody. When he loaned money, it was at high interest rates. He aggravated somebody on a land purchase once; that was bad. But nothing I would say was worthy of murder.”
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“I don’t know who the murderer is,” Fritz says. “I don’t know who they are not.”
But he believes the killer will be caught one day. “Watch over your shoulder all the time,” he says. “Revenge is best served cold; somebody is coming for them.”
Fritz says he is speaking out because of his friendship with Lewis. “Don was a friend of mine; I want to keep the ball up in the air for as long as humanly possible to get as much info as possible,” he says. “That’s my motive.”
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Earlier this month, Hillsborough County Sheriff Chad Chronister told PEOPLE he also believed that Lewis was murdered.“I believe it was a homicide,” Chronister said. “How and who’s responsible for it? That’s the unknown part right now. I wish I had more answers. I only hope, with the popularity of this Netflix series, that I’ll get those answers.”
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Lewis’ family has long suspected that Baskin, who runs the nonprofit Big Cat Rescue in Tampa, Fla., had something to do with his disappearance.
In Tiger King, Maldonado-Passage accused her of disposing of the man’s body by feeding it to her big cats.
Baskin has long denied those accusations, and on her organization’s website, she slammed Tiger King as “salacious and sensational,” saying it “has a segment devoted to suggesting, with lies and innuendos from people who are not credible, that I had a role in the disappearance of my husband Don in 1997.”
Chronister told PEOPLE that Baskin is “not a suspect at this time,” adding, “We don’t have any evidence to even call her a person of interest.”