"It wasn't his daughter," Harrison Police Chief David Hall told The Associated Press. "And why they're throwing her under the bus is beyond my ability to understand."
Authorities were called early Friday to Thomas' Westchester County home, where police said a 47-year-old man was taken to the hospital and treated for an overdose of sleeping pills. Several media outlets reported that police confirmed it was Thomas who went to the hospital.
But reached on his cell phone Friday, the 47-year-old NBA great told the New York Post he had not been treated for a sleeping pill overdose, and that it was 17-year-old daughter Lauren who had a medical issue.
It "wasn't an overdose," he said. "My daughter is very down right now. None of us are OK."
Hall forcefully refuted Thomas' statement.
"My cops ... know the difference between a 47-year-old black male and a young black female," Hall said. "These people should learn something from Richard Nixon -- it's not the crime, it's the cover-up," he added.
Voice mails and text messages from the AP were left on Thomas' cell phone Saturday. Messages left earlier with Thomas' publicist and two of his attorneys were not returned.
No suicide note was found, and police were classifying the case as an "accidental drug overdose" on "a number" of prescription sleeping pills, Hall said. Hall would not confirm the identity of the hospitalized man.
Thomas' 20-year-old son, Joshua, also said it was his sister, not his father, who required treatment.
"He's fine," the Indiana University student told the New York Daily News . "Reports of sleeping pills are false."
An ambulance and two police officers responded to a 911 call that came in from the Thomas home a couple minutes after midnight, Hall said. The victim was taken about 5 miles from the home to White Plains Hospital Center, where officials declined to identify the overdose patient.
The developments, days before the start of another season, are the latest drama in what has been a difficult year for Thomas.
He was fired as the Knicks' coach April 18 after a season of dreadful basketball, a tawdry sexual harassment lawsuit and unending chants from fans demanding his dismissal. Still, he was retained by the organization as an adviser and consultant.
"Isiah Thomas spoke with members of the New York Knicks organization and is OK," the Knicks said in a statement. "He is dealing with a family matter, and we will have no further comment. He has asked that we respect his privacy, and we will."