In California, courts are willing to allow parents to reach their own agreements as to child custody in almost all circumstances. Of course, parents are sometimes not able to reach agreement, in which case the court must decide.
California child custody law is guided by the principles that children benefit from regular, frequent, and ongoing contact with both parents, and that the court's primary concern should be the health, welfare, and safety of children. California law specifically states that neither parent should be given a preference in custody considerations based on their sex. Both parents are presumed at the outset of the custody determination to have equal rights to custody.
Within this framework, courts in San Diego and other California counties must take into account all circumstances of each case, and may consider any relevant information. Factors which may be considered include whether either parent has a history of substance abuse or of committing domestic violence or child abuse; which parent is more likely to encourage a positive relationship between the child and the other parent; the child's preference if the child is mature enough to express a preference; and the stability of a proposed living environment.