The Thai official that provided that information has backtracked somewhat: (found at this link)
...Lt. Gen. Suwat Tumrongsiskul of the Thai immigration police changed some details Friday of the account he had given of what Karr told investigators.
In a telephone interview Thursday with The Associated Press, Suwat quoted Karr as saying he had sexually assaulted the girl and given her drugs. He also told reporters before a news conference Thursday that Karr had claimed to have picked up JonBenet at her school.
On Friday, Suwat confirmed to the AP his account of the sexual assault. But asked Friday if Karr gave the girl drugs, Suwat said the suspect described the encounter with JonBenet Ramsey as "a blur."
"It may have been drugs, or it may have been something else because (Karr said) it was a blur, blur," Suwat said.
Suwat also said Friday that his statement about the girl being picked from school was based on a documentary he had seen and not the interrogation. ...
Sounds like not only is Karr a wacko, but this LE is also out after some fame and glory with fantastic stories.