Britney Spears' ex manager Sam Lufti claims he found crystal meth in the star's home.

The X Factor judge's former manager is set to bring up damaging drug claims about the period before her 2008 meltdown in his upcoming trial, according to legal documents filed about the court hearing.

The paperwork, obtained by TMZ, refers to a June 2007 incident in which "drug-sniffing dogs found a cache of crystal meth in her home" when he allegedly unleashed them on her property. "Britney should further testify that drug dogs found hot spots of drug residue in the carpeting, where her young sons [ages 1 and 3] played during visits," the documents state.

Sam insists he tried to help the singer stay off drugs before he was fired in 2009, even shampooing and eventually replacing her carpets to hide the evidence.

Britney's former manager - who is suing the star and her parents for breach of contract and defamation - also plans to quiz her over comments she made to him saying her father Jamie was an "abusive alcoholic" and a "violent racist," according to the paperwork.

Britney's father and attorney Andrew Wallet have been in charge of her legal affairs since her breakdown, but Sam is currently fighting for the singer to appear in court in person as he wants to probe her about supposed statements made by her parents claiming he drugged her and cut her phone wires. Despite her conservators claiming she is not fit enough to testify, he believes her "articulate" recent appearances alongside Simon Cowell on X Factor prove she is.