Dr. Arnold Klein

In an interview just after Michael Jackson died, Dr. Conrad Murray told police he had no clue what medications the star had been prescribed by other physicians.

Murray also says Jackson never told him he was seeing other doctors - a clue as to how he may present a defense at his ongoing involuntary manslaughter trial.

Two days after Jackson's death, Murray cited Dr. Arnold Klein, a longtime friend of Michael, as a doctor who regularly prescribed MJ drugs behind Murray's back.

Murray, by his own admission, knew this was going on. But to what degree?

According to Murray, MJ's production team complained about the singer's visits to Klein - insisting Michael's worst days on set were after he had seen Klein.

Those worst days, Dr. Conrad Murray claims, were three times a week.

During the taped interview, Murray told police, "When [he] came back [from Klein's office], he was basically wasted and required 24 hours for recovery."

Murray also claims he saw evidence of doctor-shopping by Jackson - a smattering of prescription pill bottles by his bedside, bearing other doctors' names.

Michael never spoke about it, Murray says. Whether that matters to a jury is unclear, but Murray is trying to say he didn't know how bad MJ's condition was.

Judge Michael Pastor has already ruled that Klein cannot testify.

[Photo: WENN.com]

Dr. Conrad Murray took a walloping in court Monday after the judge threw out potentially key components of the embattled physician's case that he is not guilty of involuntary manslaughter in the death of Michael Jackson.

First, Judge Michael Pastor ruled that Jackson's personal history, including all references to child molestation, will not be permitted during Murray's trial.

Then, he determined that Jackson's dermatologist and longtime friend, Dr. Arnold Klein, won't be allowed to testify when Murray is tried next month.

Pastor stated that Dr. Klein's role in MJ's care isn't relevant, and that it could confuse the jury, as could unrelated testimony about MJ's personal life.

It's the ruling on Klein that dealt the most serious blow to Murray's defense, since the physician hoped to deflect blame onto others who treated the star.

Murray's lawyers were planning on asking Dr. Arnold Klein about the Demerol that he allegedly prescribed to Michael Jackson in the days before he died.

Dr. Conrad Murray's defense team has nine former doctors of Michael Jackson on its witness list for Murray's upcoming involuntary manslaughter trial.

Among the doctors on the list is Dr. Arnold Klein, Jackson's dermatologist and friend whose treatment of the star has long been subject to scrutiny.

The last also includes Dr. Neil Ratner, who toured with Jackson in 1996 and 1997, and Dr. David Adams of Las Vegas, Nev., both anesthesiologists.

Ratner confirmed that Michael Jackson suffered from a sleep disorder, but wouldn't elaborate further. It's anticipated that Murray's lawyers, Ed Chernoff and Michael Flanagan, will grill Ratner about the specifics of his medical treatment.

In all, Dr. Murray's lawyers list 103 people who could be called at the trial, including a nurse practitioner, Cherilyn Lee, who claims Jackson asked her for Propofol in the weeks leading up to his death, but she refused to supply it.

Lee, a nurse practitioner and nutritionist who worked for Jackson, claimed in the days after his sudden death that he had asked her for Propofol in April 2009, was served with a subpoena to testify at the trial by Murray's defense.

Jason Pfeiffer, the former assistant to Michael Jackson's dermatologist, Dr. Arnold Klein, is suing him for putting MJ's life in danger, according to a new lawsuit.

Pfeiffer, who has made headlines for alleging he had a gay affair with Michael Jackson, says that "Throughout 2009, Michael was a frequent patient of Klein."

The lawsuit says, "Several times, Klein told Pfeiffer to help Michael down to the car because Michael was too drugged up and disoriented to stand on his own."

Jason Pfeiffer says he voiced his concern for Michael's "safety" because he and Klein's nurses "were worried Michael was being 'overmedicated' by Klein."

Pfeiffer says Klein simply told him to "keep his mouth shut."

Moreover, Pfeiffer claims Klein tried to sneak MJ prescription muscle relaxants in 2009 by writing a prescription in Pfeiffer's name. Pfeiffer claims he refused.

He goes on to make various other allegations against Klein:

Jason Pfeiffer, the former office manager for Michael Jackson's friend Dr. Arnie Klein, is standing by his story that he had a gay affair with the singer.

Pfeiffer says Klein is trying to sabotage his credibility because Klein is afraid Jason will incriminate him during the upcomng Dr. Conrad Murray trial.

Jason tells TMZ he's been honest all along about having a sexual relationship with the late King of Pop and is certainly standing by his story now.

Jason Pfeiffer insists, "The story is true. We had a relationship with sexual aspects, but I'm not going to make it into some grand love affair."

When the story broke last year, Klein backed up Jason's account, even going so far as to call Pfeiffer "the love of [Michael Jackson's] life."

Klein came under attack from Elizabeth Taylor shortly after, but reiterated that the story was true, saying "Michael chose who he loved."

Dr. Arnold Klein, Michael Jackson's former dermatologist and close friend, has now changed his story about MJ's alleged relationship with Jason Pfeiffer.

Pfeiffer, Klein's one-time office manager, claimed last year that he had a sexual relationship with Michael Jackson, an assertion that Klein corroborated.

Klein said that Jason Pfeiffer was the only man Michael was ever intimate with, and that Jason was "the love of [MJ's] life." Now? He says otherwise.

Pfeiffer met Jackson when he used to work for Klein.

On his Facebook page, Klein (above, left) says that "Allegations about ... Jason being Michael Jackson's lover are ridiculous. That story was made up ... "

It did seem a little far-fetched at the time, although, given that Klein personally backed Jason's story up to TMZ, it's hard to know what to believe here.

Klein also scoffs at allegations (indirectly made by Dr. Conrad Murray and others) that he contributed to MJ's death, saying he only tried to help him.

"I made two interventions on Michael's Propofol Abuse myself."

Charged with involuntary manslaughter, Dr. Conrad Murray will likely argue that Michael Jackson killed himself with a lethal dose of Propofol.

Even if that were true (and it's a stretch), it still wouldn't get Murray off the hook. The treatment he gave MJ was suspect for myriad reasons.

To that end, Murray's lawyers just filed documents pointing fingers at none other than Dr. Arnold Klein - Jackson's longtime doctor and friend.

Murray claims that Klein addicted Jackson to Demerol and other powerful narcotics. It's part of his plan to establish Michael as a lost cause physically.

Murray's legal team claims Klein fueled MJ's addiction as recently as 2009 by giving him scores of Demerol injections in the months prior to his death.

He may have a point there. In the months before Jackson died, Dr. Arnold Klein gave Jackson 51 Demerol injections. But is it relevant to the case?

The docs claim it is for this reason: "Due to Mr. Klein's actions, Mr. Jackson became physiologically and psychologically dependent on Demerol."

Murray's team says Dr. Arnold Klein, who is also the rumored biological father of MJ's kids Paris and Prince, "is a relevant, highly material witness."

Dr. Conrad Murray ...

It goes without saying at this point, but Michael Jackson did not go out on a high note in 2009. Stress, desperation and medication were all taking their toll.

The star was so worried he couldn't perform his 50 London concerts, he worried out loud that promoter AEG would cut him loose and he'd have nothing left.

To illustrate just how stressed out he was, he would wonder aloud if he, one of the richest entertainers in history, would end up working at McDonald's.

NOT OKAY: Michael Jackson was exhibiting all the warning signs.

Karen Faye, Michael's hairstylist for a quarter century, was interviewed by LAPD detectives days after MJ died, and described some of his innermost fears.

Faye told cops, "He was scared to death because AEG was funding everything. He said he would have to work at McDonalds if he didn't do these shows."

Faye also said she felt Michael was "self-sabotaging" with drugs because Jackson couldn't do all 50 shows and was in dire need of psychological help.

Others have speculated he was too weak to perform for years.

The embattled Dr. Conrad Murray is challenging a lawsuit filed against him by the father of the late Michael Jackson - and asking why another doc isn't a defendant.

Murray is going after Michael's longtime physician and friend, Dr. Arnold Klein, claiming Klein is at least partly to blame for the singer's untimely, June 2009 death.

As such, Murray says, Klein should be named in Joe Jackson's wrongful death lawsuit. MJ's mother and kids also filed suit against AEG, Michael's concert promoter.

Dr. Conrad Murray (left) is putting some of the blame on Dr. Arnie Klein.

Dr. Murray was on AEG's payroll, serving as Michael's personal physician at the time of his death. Conrad faces involuntary manslaughter charges in criminal court.

His legal declaration today comes in response to Joe Jackson's decision not to name Dr. Arnold Klein as one of the physicians allegedly responsible for MJ's death.

Murray claims: "Dr. Klein may have been medicating Michael Jackson up until or even beyond June 18, 2009, less than one week before Michael Jackson's death."

Dr. Arnold Klein, Michael Jackson's close friend, has come out swinging against Joe Jackson, claiming Michael's father is a guy who cares only about money.

Klein was responding to claims Joe made about Michael's mother and how Katherine was responsible for Michael's death when he told TMZ the following:

"Michael was very close to Katherine, but Joe talked to him too, but all Joe ever wanted to talk about was business. Everything Joe utters is nonsensical."

Pretty much.

Joe claims that he warned his estranged wife about Michael's failing health last year, but she was afraid of violating his privacy and refused to intervene.

Michael Jackson's father Joe.

Arnie has made numerous headlines in the past year, first as the rumored biological father of Michael's children, a rumor he has never emphatically denied.

Then more recently, he took serious heat for backing up former employee Jason Pfeiffer's claim that Michael Jackson was gay and Pfeiffer had an affair with him.

Now, however, the singer's confidant and former dermatologist is growing increasingly tired of all things Michael and wishes he could finally rest in peace.

Klein says he's over the drama: "I'm no longer interested in the Sodom and Gomorrah show on Havenhurst (the family home). My primary concern is the welfare of the children, especially Michael's, and the preservation of Michael's memory."