Michael Jackson Hoax Death

That's incorrect.  The California Probate Code states:

6112.  (a) Any person generally competent to be a witness may act as
a witness to a will.

   (b) A will or any provision thereof is not invalid because the
will is signed  by an interested witness.

   (c) Unless there are at least two other subscribing witnesses to
the will who are disinterested witnesses, the fact that the will
makes  a devise to a subscribing witness creates a presumption that
the witness procured the devise by duress,  menace, fraud, or undue
influence.  This presumption is a presumption affecting the burden of
proof.  This presumption does not apply where the witness is a
person to whom the devise is made solely in a fiduciary capacity.

   (d) If a devise made by the will to an interested witness fails
because the presumption established by subdivision (c) applies to the
devise and the witness fails to rebut the presumption, the
interested witness shall take such proportion of the devise made to
the witness in the will as does not exceed the share of the estate
which would be distributed to the witness if the will were not
established.  Nothing in this subdivision affects the law that
applies where it is established that the witness procured a devise by
duress, menace, fraud, or undue influence.