When detectives raided the Billie Jean singer’s home in November 2003 as part of the child sex abuse investigation against him they found a trove of twisted photographs he had stashed.
A previously unseen police report claims there were at least seven collections which showed boys in their teenage years - and in some cases younger - fully nude or partially clothed in Jackson's bedroom.
One of the collections, Taormina Wilhelm Von Gloeden, is described in court papers as: 'Nude photos of teenage boys from late 1800s.'
More than 70 members of the Santa Barbara County District Attorney's Office and Sheriff's Department raided the home while Jackson was in Las Vegas.
Read more: Michael Jackson paid £134m hush money to keep as many as 20 sex abuse victims quiet, lawyers claim
It came at the same time an arrest warrant had been issued for the singer which saw Jackson later turn himself into police when he returned to California.
“He also had disgusting and downright shocking images of child torture, adult and child nudity, female bondage and sadomasochism."
The investigator added: “Based on my training, this type of material can be used as part of the "grooming" process, by which people (those seeking to molest children) lower the inhibitions of their intended victims and facilitate the molestation of said victims.”
The items said to have been found included 'a book depicting nude children' found in the singer's 'arcade room'.
Santa Barbara Senior Assistant District Attorney Ron Zonen, who was part of the prosecution team that took on Jackson in court, said: “A lot of this stuff was used to desensitise the children, and Michael admitted taking one child after another into bed with him for long periods of time.
Police also searched a rented storage space after Santa Barbara County Sheriff’s Detective Craig Bonner requested a warrant.
The request to search Shurgard Storage came after police were tipped of Jackson had moved items into the unit after the investigation was launched.
According to the report materials seized were “notes, diaries, documents, photographs, audiotapes and videotapes", along with more than 80 video recordings and computer hard drives.
The investigator added: “The documents collected by the Santa Barbara County Sheriff’s Department paint a dark and frightening picture of Jackson.
“He also had disgusting and downright shocking images of child torture, adult and child nudity, female bondage and sadomasochism.”
The superstar faced up to 20 years in prison but was cleared of all charges in June 2005.
Since he died aged 50 on June 25, 2009, Jackson’s estate has raked in over £1.36 billion.
