The opinion
HULL, J.
I concur in the result.
The law in this area is a quagmire; there is no firm ground beneath one’s feet. I agree only that we should remand this matter to the trial court for further evidence and a more complete record. I do so with some reluctance and I write separately to express my reservations.
Even though this mandamus action is brought on behalf of only three petitioners, its reach, if successful, will presumably extend to any person whose education has been delayed at any time by virtue of their having suffered a disability. On this record, that population is unknown and therefore the cost to the state of a decision in petitioners’ favor is unknown. I am willing to return the matter to the trial court to allow the parties to present evidence on this issue, but I suspect that the number of people affected by a *275 ruling in petitioners’ favor is not only unknown but unknowable, either this year, or in future years. I doubt that it is possible to judge accurately, or to even make an informed estimate of, the fiscal impact of a ruling that bars application of the completion rule to an unknown number of persons. And, if that number is as large as I think it may be, a ruling in petitioners’ favor may well have the practical effect of, essentially, writing the completion rule out of the statute. However, caution suggests we should have a record that more fully explores that issue, and for that reason I agree the matter should be returned to the trial court.
The majority remands the matter to the trial court “to consider the cost of accommodating plaintiffs and all other persons in the state similarly situated.” (Maj. opn., ante, at p. 273.) To comply with this remand order the trial court will be required to consider, in part, the definition of a “disability.”
Code of Federal Regulations, title 28, section 35.104 (hereafter section 35.104) defines “disability” with respect to an individual as “a physical or mental impairment that substantially limits one or more of the major life activities of such an individual; a record of such an impairment; or being regarded as having such an impairment.” (§ 35.104 (2002).)
Section 35.104 defines “physical or mental impairment” as “[a]ny physiological disorder or condition, cosmetic disfigurement, or anatomical loss affecting one or more of the following body systems: Neurological, musculoskeletal, special sense organs, respiratory (including speech organs), cardiovascular, reproductive, digestive, genitourinary, hemic and lymphatic, skin, and endocrine” or “[a]ny mental or psychological disorder such as mental retardation, organic brain syndrome, emotional or mental illness, and specific learning disabilities.” (§ 35.104 (2002).)
Section 35.104 also provides that “[t]he phrase physical or mental impairment includes, but is not limited to, such contagious and noncontagious diseases and conditions as orthopedic, visual, speech and hearing impairments, cerebral palsy, epilepsy, muscular dystrophy, multiple sclerosis, cancer, heart disease, diabetes, mental retardation, emotional illness, specific learning disabilities, HIV disease (whether symptomatic or asymptomatic), tuberculosis, drug addiction, and alcoholism.” (§ 35.104 (2002).)
If we are guided, as I think we should be, by the United States Supreme Court’s holdings in Olmstead v. L. C. (1999) 527 U.S. 581 [ 119 S.Ct. 2176 , 144 L.Ed.2d 540 ] and School Bd. of Nassau County v. Arline (1987) 480 U.S. 273 [ 94 L.Ed.2d 307 , 107 S.Ct. 1123 ], the trial court must decide from the evidence presented the number of persons in the State of California who will *276 be unable to complete high school before age 19 due to a disability. The trial court will then have to determine the cost of continuing those person’s benefits to age 19 and decide whether, given the resources available to CalWORKS, that cost imposes an undue financial burden on the program. If it does, the requested accommodation is not reasonable and is not required by the Americans with Disabilities Act.
I have difficulty understanding how we can determine whether the accommodation sought by petitioners will impose an undue financial burden on the state when one cannot know how many people are entitled to that accommodation, or how many people will be entitled to that accommodation in the future. We may be requiring the state to prove what cannot be proven.
I note also that the financial burden of the requested accommodation may be greater, or less, in a given fiscal year, depending on the number of people who qualify for it and depending also on the state’s and the CalWORKS program’s resources. What is “undue” may well change from year to year. If the Americans with Disability Act requires this accommodation, except where it imposes an undue financial burden, must the task of determining that burden become an annual exercise? Will the completion rule be applicable to those with disabilities in some years but not in others? Given the majority opinion’s analysis of the issue before us, those results seem logically to follow.
For all of these reasons, I am inclined to defer to the Legislature’s implied determination that the completion rule is an essential eligibility requirement for the CalWORKS program, that is, the program’s purposes cannot be achieved without the rule. But I am willing to wait for a complete record and consider what that record might show. I agree with the remand.