CA Fam Code Section 7554

(a)

If the court finds that the conclusions of all the experts, as disclosed by the evidence based upon the tests, are that the alleged father is not the father of the child, the question of paternity shall be resolved accordingly.

(b)

If the experts disagree in their findings or conclusions, or if the tests show the probability of the alleged father’s paternity, the question, subject to Section 352 of the Evidence Code, shall be submitted upon all the evidence, including evidence based upon the tests.