Michael Jackson's siblings resume attack on will

The five-page document is straightforward and simple, and many key provisions of how Jackson's estate is constructed are set out in a trust. That document has never been publicly released.

Many of the misgivings stem from the will's final page, which bears the signatures of three witnesses who claim Jackson signed the document on July 7, 2002, in Los Angeles. Jackson's family points out that the singer was in New York on that day, a point the Rev. Al Sharpton recently bolstered by showing video of the "Thriller" singer appearing with him at an event in Harlem that day.

"I don't think that kind of extrinsic fraud would be enough to overturn the order admitting the will to probate," said Marshall Oldman, a Los Angeles probate attorney who represented Peter Falk's wife in a conservatorship proceeding.

He said Jackson's siblings' only valid argument is that they did not receive proper notice that their brother's will had been accepted into probate. Superior Court Judge Mitchell Beckloff accepted the will in November 2009. Any challenge would have had to been filed within four months, Oldman said.

The California 2nd District Court of Appeal noted in an October 2010 ruling against the singer's father that the period to challenge the will had already expired. Even if the will were thrown out, the court noted, California law would require the estate to benefit Michael Jackson's children.

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"I don't see how you come in three years later, and say, 'oh, by the way, the will's a fraud, a forgery, because he wasn't in L.A. when he was purported to be,'" said Howard Klein, a probate attorney for nearly 50 years and partner in the Los Angeles firm Feinberg Mindel Brandt Klein & Kline. "It's something that should have been brought up a long time ago."

Randy Jackson — in comments on Twitter and to Sharpton on his MSNBC show last week — has repeatedly accused the estate's executors of criminal conduct. Both Klein and Oldman said even if the executors were charged with wrongdoing, it wouldn't open the door for more of Jackson's relatives to gain access to the estate. Jackson's children are deemed his heirs without the will, and a 1997 version lodged with the court but never publicly released also doesn't name the singer's siblings as beneficiaries of his estate.

Klein said even if Jackson or other siblings try to challenge the document, their bid will likely be rejected because it is too late. The judge could also rule, as he did against family patriarch Joe Jackson, that because he isn't a beneficiary of the will, he isn't entitled to contest it.