DOVER, Del. – To many people, Dr. Melvin Morse was a brilliant pediatrician at a renowned children’s hospital and a best-selling author who parlayed his research on near-death experiences into appearances on “Larry King Live” and “The Oprah Winfrey Show.”

Away from the spotlight, however, Morse was tormented by personal and financial problems and, according to court records, wrestled with depression, substance abuse and even suicidal thoughts. His latest trouble involves allegations of waterboarding his 11-year-old stepdaughter, using the simulated drowning technique to bring her to “a possible near-death state,” police have said.

Based on his work involving children’s near-death experiences, police suggested he may have been experimenting on her.

Morse, 58, was accused in July of grabbing his daughter by the ankle and dragging her across a gravel driveway. When police did a follow-up interview last week, the girl said Morse had held her face under running water at least four times since 2009, using faucets in the kitchen, bathroom sink and bathtub. Her mother, Pauline Morse, witnessed some of the waterboarding but did nothing to stop it, police said.

Both Melvin and Pauline Morse are free on bail. They face a preliminary hearing Thursday on felony endangerment and conspiracy charges.

In an interview with The Associated Press, Melvin Morse called the charges an overreaction by authorities. An attorney for Morse, Joe Hurley, said the idea that Morse was experimenting on his own daughter was “the sheerest of speculation.”

Morse began researching near-death experiences in children about three decades ago after the near drowning of one of his patients. He was fascinated by the spiritual experiences the girl, and other children, described to him, including images of light, heaven and tunnels.

He sought to prove that drugs were causing the hallucinations, though he said his research proved otherwise. In 1990, he published “Closer to the Light,” which spent several weeks on the New York Times bestseller list. Television shows had him on to speak about paranormal experiences.

He worked for Seattle Children’s Hospital and Seattle Magazine listed Morse among the city’s best doctors for more than a decade beginning in 1995, according to Morse’s website. But by 2007, Morse had retired from full-time medical practice and moved to Delaware. Hepatitis C that he contracted in 1998 while treating children became too much of a toll on his health for him to continue working full time and he was declared disabled, he said.

While Morse once earned a six-digit income, he has struggled financially for years and owes tens of thousands of dollars in back taxes.

“I have the most ordinary reasons for that — the collapse of my income and my first divorce,” Morse said. “I do not have an adversarial relationship with the IRS. … I’ll eventually repay my taxes.”

Morse’s financial problems are outlined in court records from a contentious divorce and custody battle with his first wife.

Morse’s ex-wife, Allison Morse, claimed her ex-husband has abused prescription drugs and made false accusations against their adopted children that led to criminal charges against them.

“He is a pathological liar and he makes stuff up about his own children,” she told the AP.

At the same time, she said Morse was a good dad and never abused their three adopted children during their marriage