The lead investigator says Michael Jackson's accuser claimed the singer molested him five to seven times.
But he said the boy could only describe two of the alleged incidents in detail.
The prosecution asked about the numbers to account for changing stories that the accuser and his brother and sister told investigators.
The boy himself has testified to only two molestations but said he believed there may have been more.
The possibility of him not being aware or fully aware at certain times has been raised in testimony by the boy's brother, who said he twice saw his brother being molested while asleep.