DOVER, Del. — A Delaware pediatrician who achieved national recognition for his research into near-death experiences involving children may have been experimenting on his 11-year-old stepdaughter by waterboarding her, police said in court documents.

The possible link between Dr. Melvin Morse’s research and the waterboarding allegations was revealed in an affidavit for a search warrant for Morse’s computers. The document was obtained Tuesday by The Associated Press.

According to the affidavit, Dr. Melvin Morse brought the girl ‘‘to a possible near-death state from the simulation of drowning.’’

‘‘This ‘waterboarding’ that he has performed . . . would fall into the area of study he practices,’’ police said in the affidavit. ‘‘It is logical that he has therefore written about and/or researched the topic of ‘waterboarding.’’’

Joe Hurley, an attorney for Morse, said the idea that Morse was experimenting on his own daughter is ‘‘the sheerest of speculation.’’

Morse, who faces a preliminary hearing Thursday on felony child endangerment and conspiracy charges, has authored several books and articles on paranormal science and near-death experiences.

He has appeared on ‘‘Larry King Live’’ and the ‘‘The Oprah Winfrey Show’’ to discuss his research on out-of-body experiences.

Morse said Monday that the charges against him are an overreaction from authorities who were criticized after a child sex-abuse scandal involving another pediatrician.

The allegations of waterboarding came after Morse’s 11-year-old stepdaughter told investigators last week that her father had disciplined her by holding her face under a running faucet at least four times since 2009.