When a child support order is issued, it can be made retroactive to an earlier date.
The issue of retroactivity in Paternity actions (child born to unmarried parents) in non-welfare cases, was decided by the California Supreme Court, in County of Santa Clara vs. Perry (1998) 18 Cal. 4th 435. Issue: When a child support order is issued, to what date, is that order made retroactive to? (Note, arrearages would incur 10% legal interest.] Perry decision involved cases under the federal "IV-D" program, those initiated by the Department of Child Support, §17400 cases.
Several cases had reached the Supreme Court, because the courts in the North county were ruling differently than the courts in the South county, and ultimately the Supreme Court consolidated them and ruled in favor of the North County.
Family Code §4009 governs the effective date of child support orders and after the 1998 Perry decision, the legislation twice amended the statute (1999/2004) so that it now reads: "An original order for child support may be made retroactive to the date of filing the petition, complaint, or other initial pleading...." (Back then, it read: ... retroactive to the date of filing the notice of motion....")
Back to Perry in 1998. The question there was, whether an order for child support can be made retroactive to the date the original complaint was filed rather than the date a notice of motion was served. (That is because in one of those cases, the complaint was filed in 1989 but because the Father had moved several times, they were not able to locate him and have him served until 1991.)
[Side Note: §4009 deals with "original order." For modification of orders, we look at §3653 which states that modification/terminations are retroactive to the date of filing a motion or any susequent date.]
Back to Perry in 1998. One of the cases (the North) was saying that a complaint does not constitutes notice and other case (the South) was saying a complaint is the functional equivalent of a notice of motion. The 1998 Perry supreme court decision said: (1) A complaint and a noticed motion are quite distinct. The complaint used in paternity proceedings does not satisfy the statutory requirements for a noticed motion. (2) §4009 applies alike to dissolution actions and paternity actions. (3) In either case, the retroactivity of the support order is determined by the date of filing of the notice of motion or order to show case. (4) The statute cannot reasonably be read to permit courts to make a support order retroactive to a date prior to the filing of the notice of motion.
As stated, after the decision was issued, the legislator changed the retroactivity provision. But in practice, the Courts continue to make the orders retroactive to the date of the filing of the motion or a later date and not the filing of the complaint. (Still, it depends on the judge.)
Perry was a non-welfare case. In welfare cases, the issue was raised in County of Riverside v. Burt (2000) 78 Cal. App. 4th 28, where the mother had received public assistance from the Department of Social Services. There the court said that the Perry decision does not limit retroactivity to child support orders to the date of filing of the notice of motion, that the noncustodial parent is liable for support commencing from the payment of AFDC benefits, subject only to the three-year statute of limitations and his or her reasonable ability to pay.