California law holds that parents can obtain an order from the court allowing them to move children away from their current residence, even if that creates a situation where the visitation or custody of the other parent is reduced.  The standard, as always, is the vague and ambiguous “best interests of the child” which as usual gives the court virtually unfettered discretion if it can articulate a rationale for the order, and such an order can almost certainly not be overturned upon appeal.

The vast majority of the case law revolves around custodial parents taking the children and the noncustodial parent staying behind.  Custodial parents, in those cases, have presumptive rights, meaning the odds are in their favor that the court will grant the order to move.  The “primary caregiver” (aka mother) does not have the burden.

In essence,  the relocating parent has no burden of showing that the move is necessary but in fact the noncustodial parent seeking to change the order for legal and physical custody takes on the burden of convincing the court that a change in custody (because preventing the custodial parent from moving would be a change in custody) is in the child’s best interest. This burden is substantial, and must establish that as a result of the relocation the child “will suffer detriment rendering it essential or expedient” for the child’s welfare that there be a change. “The dispositive issue is … not whether relocating is itself ‘essential or expedient’ either for the welfare of the custodial parent or the child, but whether a change in custody is ‘essential or expedient for the welfare of the child.’ ” 

All of this is not necessarily helpful when dealing with parents who share joint legal and physical custody.  Although the dizzying array of rules read like a shopping list of therapist suggestions, the bottom line is this: what is in the best interests of the children.