## Facts

- Brad Michael L. was born on November 7, 1977, to Catherine R.L., who was unmarried at the time; paternity was not established at birth.
- Lee D. did not know of Brad’s existence for approximately the first fifteen years of Brad’s life.
- Around 1992, Catherine contacted Lee seeking his acknowledgment of paternity; Lee did not respond.
- Catherine was time-barred from filing a paternity action, but Brad (through a guardian ad litem) filed to establish paternity and obtain support.
- Blood tests established Lee as Brad’s biological father.
- Lee was married with two other children and had substantial income from farming and logging.
- The circuit court adjudicated Lee as the father and ordered prospective child support of $500 per month, but denied any past support based largely on Lee’s lack of notice and constitutional and fairness concerns.

## Issues

1. Whether a court may order past child support back to the child’s birth under Wis. Stat. § 767.51(4) when the father was unaware of the child.
2. Whether ordering such past support constitutes an unconstitutional ex post facto application of the statute.
3. Whether a father’s ignorance of paternity is a proper factor in setting the amount or availability of support.
4. Whether marital property principles may be used to determine the payor’s base income for child support.
5. Whether the court may exclude depreciation in calculating a self-employed payor’s income for support.
6. Whether a court may contemplate post-majority modification of child support to address future college costs absent a proper legal basis.

## Decision

- The court of appeals affirmed the paternity adjudication.
- The court reversed the child-support determinations and remanded for recalculation consistent with law.
- The court held past child support may be ordered back to birth under § 767.51(4), notwithstanding the father’s lack of knowledge.
- The court rejected the ex post facto rationale because the support obligation is civil and remedial, enforcing a preexisting duty.
- The court held ignorance of paternity is not a proper factor reducing or eliminating a child’s entitlement to support.
- The court held marital property concepts should not be imported into child-support income determinations.
- The court held the trial court erred in its treatment of depreciation and required an income calculation reflecting true economic capacity.
- The court rejected the notion of open-ended post-majority modification to address college expenses absent statutory or other authorized grounds.

## Legal Principles

- In a paternity action, a court may order past child support back to the child’s birth under Wis. Stat. § 767.51(4), even if the father lacked notice of the child.
- Ex post facto limits apply to punitive criminal (or quasi-criminal) laws and generally do not invalidate remedial civil child-support enforcement mechanisms.
- A child’s right to support is not reduced because the biological parent was unaware of the child; the relevant inquiry centers on statutory support factors and the child’s needs.
- Child-support income calculations must follow the governing child-support statutes and administrative rules; marital property allocation doctrines are not controlling for defining income.
- Depreciation for self-employed obligors must be analyzed to reflect actual economic capacity and to prevent understating income through accounting treatment.
- Post-majority support for college costs is not presumed; courts must act within the limits of authorized support obligations.

## Conclusion

The court required a recalculation of support because Wisconsin law permits past support back to birth in paternity actions and does not allow denial of support based on the father’s ignorance of paternity, constitutional concerns tied to ex post facto doctrine, or income calculations derived from marital property concepts or inaccurate treatment of depreciation.


In re Paternity of Brad Michael L., 210 Wis. 2d 437, 564 N.W.2d 354 (Wis. Ct. App. 1997)