delivered the opinion of the Court.
The New York City Transit Authority refuses to employ persons who use methadone. The District Court found that this policy violates the Equal Protection Clause of the Fourteenth Amendment. In a subsequent opinion, the court also held that the policy violates Title VII of the Civil Rights Act of 1964. The Court of Appeals affirmed without reaching the statutory question. The departure by those courts from the procedure normally followed in addressing statutory and con*571stitutional questions in the same case, as well as concern that the merits of these important questions had been decided erroneously, led us to grant certiorari.1 438 U. S. 904. We now reverse.
The Transit Authority (TA) operates the subway system and certain bus lines in New York City. It employs about 47,000 persons, of whom many — perhaps most — are employed in positions that involve danger to themselves or to the public. For example, some 12,300 are subway motormen, towermen, conductors, or bus operators. The District Court found that these jobs are attended by unusual hazards and must be performed by “persons of maximum alertness and competence.” 399 F. Supp. 1032, 1052 (SDNY 1975). Certain other jobs, such as operating cranes and handling high-voltage equipment, are also considered “critical” or “safety sensitive,” while still others, though classified as “noncritical,” have a potentially important impact on the overall operation of the transportation system.2
TA enforces a general policy against employing persons *572who use narcotic drugs. The policy is reflected in Rule 11 (b) of TA’s Rules and Regulations.
“Employees must not use, or have in their possession, narcotics, tranquilizers, drugs of the Amphetamine group or barbiturate derivatives or paraphernalia used to administer narcotics or barbiturate derivatives, except with the written permission of the Medical Director — Chief Surgeon of the System.”
Methadone is regarded as a narcotic within the meaning of Rule 11 (b). No written permission has ever been given by TA's medical director for the employment of a person using methadone.3
*573The District Court found that methadone is a synthetic narcotic and a central nervous system depressant. If injected into the bloodstream with a needle, it produces essentially the same effects as heroin.4 Methadone has been used legitimately in at least three ways — as a pain killer, in “detoxification units” of hospitals as an immediate means of taking addicts off of heroin,5 and in long-range “methadone maintenance programs” as part of an intended cure for heroin addiction. See 21 CNR § 310.304 (b) (1978). In such programs the methadone is taken orally in regular doses for a prolonged period. As so administered, it does not produce euphoria or any pleasurable effects associated with heroin; on the contrary, it prevents users from experiencing those effects *574when they inject heroin, and also alleviates the severe and prolonged discomfort otherwise associated with an addict’s discontinuance of the use of heroin.
About 40,000 persons receive methadone maintenance treatment in New York City, of whom about 26,000 participate in the five major public or semipublic programs,6 and 14,000 are involved in about 25 private programs.7 The sole purpose of all these programs is to treat the addiction of persons who have been using heroin for at least two years.
Methadone maintenance treatment in New York is largely governed by regulations promulgated by the New York State Drug Abuse Control Commission. Under the regulations, the newly accepted addict must first be detoxified, normally in a hospital. A controlled daily dosage of methadone is then prescribed. The regulations require that six doses a week be administered at a clinic, while the seventh day’s dose may be taken at home. If progress is satisfactory for three months, additional doses may be taken away from the clinic, although *575throughout most of the program, which often lasts for several years, there is a minimum requirement of three clinic appearances a week. During these visits, the patient not only receives his doses but is also counseled and tested for illicit use of drugs.8
The evidence indicates that methadone is an effective cure for the physical aspects of heroin addiction. But the District Court also found “that many persons attempting to overcome heroin addiction have psychological or life-style problems which reach beyond what can be cured by the physical taking of doses of methadone.” 399 F. Supp., at 1039. The crucial indicator of successful methadone maintenance is the patient’s abstinence from the illegal or excessive use of drugs and alcohol. The District Court found that the risk of reversion to drug or alcohol abuse declines dramatically after the first few months of treatment. Indeed, “the strong majority” of patients who have been on methadone maintenance for at least a year are free from illicit drug use.9 But a significant *576number are not. On this critical point, the evidence relied upon by the District Court reveals that even among participants with more than 12 months’ tenure in methadone maintenance programs, the incidence of drug and alcohol abuse may often approach and even exceed 25%.10
This litigation was brought by the four respondents as a class action on behalf of all persons who have been, or would in the future be, subject to discharge or rejection as employees of TA by reason of participation in a methadone maintenance program. Two of the respondents are former employees of TA who were dismissed while they were receiving methadone treatment.11 The other two were refused employment by TA, one both shortly before and shortly after the successful conclusion of his methadone treatment,12 and the other while he *577was taking methadone.13 Their complaint alleged that TA’s blanket exclusion of all former heroin addicts receiving methadone treatment was illegal under the Civil Rights Act of 1866, Rev. Stat. § 1977, 42 U. S. C. § 1981, Title VII of the Civil Rights Act of 1964, 78 Stat. 253, as amended, 42 U. S. C. § 2000e et seg., and the Equal Protection Clause of the Fourteenth Amendment.
The trial record contains extensive evidence concerning the success of methadone maintenance programs, the employ-ability of persons taking methadone, and the ability of prospective employers to detect drug abuse or other undesirable characteristics of methadone users. In general, the District Court concluded that there are substantial numbers of methadone users who are just as employable as other members of the general population and that normal personnel-screening procedures — at least if augmented by some method of obtaining information from the staffs of methadone programs — would enable TA to identify the unqualified applicants on an individual basis. 399 F. Supp., at 1048-1051. On the other hand, the District Court recognized that at least one-third of the persons receiving methadone treatment — and probably a good many more — would unquestionably be classified as unemployable.14
*578After extensively reviewing the evidence, the District Court briefly stated its conclusion that TA’s methadone policy is unconstitutional. The conclusion rested on the legal proposition that a public entity “cannot bar persons from employment on the basis of criteria which have no rational relation to the demands of the jobs to be performed.” Id., at 1057. Because it is clear that substantial numbers of methadone users are capable of performing many of the jobs at TA, the court held that the Constitution will not tolerate a blanket exclusion of all users from all jobs.
The District Court enjoined TA from denying employment to any person solely because of participation in a methadone maintenance program. Recognizing, however, the special responsibility for public safety borne by certain TA employees and the correlation between longevity in a methadone maintenance program and performance capability, the injunction authorized TA to exclude methadone users from specific categories of safety-sensitive positions and also to condition eligibility on satisfactory performance in a methadone program for at least a year. In other words, the court held that TA could lawfully adopt general rules excluding all methadone users from some jobs and a large number of methadone users from all jobs.
Almost a year later the District Court filed a supplemental opinion allowing respondents to recover attorney’s fees under 42 U. S. C. § 2000e-5 (k). This determination was premised on the court’s additional holding that TA’s drug policy violated Title VII. Having already concluded that the blanket *579exclusion was not rationally related to any business needs of TA, the court reasoned that the statute is violated if the exclusionary policy has a discriminatory effect against blacks and Hispanics. That effect was proved, in the District Court’s view, by two statistics: (1) of the employees referred to TA’s medical consultant for suspected violation of its drug policy, 81% are black or Hispanic; (2) between 62% and 65% of all methadone-maintained persons in New York City are black or Hispanic. 414 F. Supp. 277, 278-279 (SDNY 1976). The court, however, did not find that TA’s policy was motivated by any bias against blacks or Hispanics; indeed, it expressly found that the policy was not adopted with a discriminatory purpose. Id., at 279.
The Court of Appeals affirmed the District Court’s constitutional holding. 558 F. 2d 97. While it declined to reach the statutory issue, it also affirmed the award of attorney’s fees under the aegis of the recently enacted Civil Rights Attorney’s Fees Awards Act of 1976, 42 U. S. C. § 1988, which provides adequate support for an award of legal fees to a party prevailing on a constitutional claim.15
After we granted certiorari, Congress amended the Rehabilitation Act of 1973, 87 Stat. 357, 29 U. S. C. § 701 et seq., to prohibit discrimination against a class of “handicapped individuals” that arguably includes certain former drug abusers and certain current users of methadone. Pub. L. 95-602, 92 Stat. 2984. Respondents argue that the amendment now *580mandates at least the prospective relief granted by the District Court and the Court of Appeals and that we should therefore dismiss the writ as improvidently granted. We are satisfied, however, that we should decide the constitutional question presented by the petition. Before doing so, we shall discuss (1) the effect of the Rehabilitation Act on this case; and (2) the error in the District Court's analysis of Title VII.
I
Respondents contend that the recent amendment to § 7 (6) of the Rehabilitation Act proscribes TA's enforcement of a general rule denying employment to methadone users.16 Even if respondents correctly interpret the amendment, and even if they have a right to enforce that interpretation,17 the case *581is not moot since their claims arose even before the Act itself was passed,18 and they have been awarded monetary relief.19 Moreover, the language of the statute, even after its amendment, is not free of ambiguity,20 and no administrative or judicial opinions specifically considering the impact of the statute on methadone users have been called to our attention. Of greater importance, it is perfectly clear that however we might construe the Rehabilitation Act, the concerns that prompted our grant of certiorari would still merit our attention.21 We therefore decline to give the statute its first judicial construction at this stage of the litigation.
*582II
Although respondents have consistently relied on both statutory and constitutional claims, the lower courts focused primarily on the latter. Thus, when the District Court decided the Title VII issue, it did so only as an afterthought in order to support an award of attorney's fees; the Court of Appeals did not even reach the Title VII issue. We do not condone this departure from settled federal practice. “If there is one doctrine more deeply rooted than any other in the process of constitutional adjudication, it is that we ought not to pass on questions of constitutionality . . . unless such adjudication is unavoidable.” Spector Motor Service, Inc. v. McLaughlin, 323 U. S. 101, 105. Before deciding the constitutional question, it was incumbent on those courts to consider whether the statutory grounds might be dispositive.22 What*583ever their reasons for not doing so,23 we shall first dispose of the Title VII issue.24
The District Court’s findings do not support its conclusion *584that TA’s regulation prohibiting the use of narcotics, or its interpretation of that regulation to encompass users of methadone, violated Title YII of the Civil Rights Act.
A prima facie violation of the Act may be established by statistical evidence showing that an employment practice has the effect of denying the members of one race equal access to employment opportunities. Even assuming that respondents have crossed this threshold, when the entire record is examined it is clear that the two statistics on which they and the District Court relied do not prove a violation of Title VII.25
First, the District Court noted that 81% of the employees referred to TA’s medical director for suspected violation of its narcotics rule were either black or Hispanic. But respondents *585have only challenged the rule to the extent that it is construed to apply to methadone users, and that statistic tells us nothing about the racial composition of the employees suspected of using methadone.26 Nor does the record give us any information about the number of black, Hispanic, or white persons who were dismissed for using methadone.
Second, the District Court noted that about 63% of the persons in New York City receiving methadone maintenance in public programs — i. e., 63%- of the 65% of all New York City methadone users who are in such programs27 — are black or Hispanic. We do not know, however, how many of these persons ever worked or sought to work for TA. This statistic therefore reveals little if anything about the racial composition of the class of TA job applicants and employees receiving methadone treatment. More particularly, it tells us nothing about the class of otherwise-qualified applicants and employees who have participated in methadone maintenance *586programs for over a year — the only class improperly excluded by TA’s policy under the District Court’s analysis. The record demonstrates, in fact, that the figure is virtually irrelevant because a substantial portion of the persons included in it are either unqualified for other reasons — such as the illicit use of drugs and alcohol28 — or have received successful assistance in finding jobs with employers other than TA.29 Finally, we have absolutely no data on the 14,000 methadone users in the private programs, leaving open the possibility that the percentage of blacks and Hispanics in the class of methadone users is not significantly greater than the percentage of those minorities in the general population of New York City.30
*587At best, respondents’ statistical showing is weak; even if it is capable of establishing a prima facie case of discrimination, it is assuredly rebutted by TA’s demonstration that its narcotics rule (and the rule’s application to methadone users) is “job related.” 31 The District Court’s express finding that the rule was not motivated by racial animus forecloses any claim in rebuttal that it was merely a pretext for intentional discrimination. 414 F. Supp., at 279. We conclude that respondents failed to prove a violation of Title VII. We therefore must reach the constitutional issue.
Ill
The Equal Protection Clause of the Fourteenth Amendment provides that no State shall “deny to any person within its jurisdiction the equal protection of the laws.” The Clause announces a fundamental principle: the State must govern impartially. General rules that apply evenhandedly to all persons within the jurisdiction unquestionably comply with this principle. Only when a governmental unit adopts a rule that has a special impact on less than all the persons subject *588to its jurisdiction does the question whether this principle is violated arise.
In this case, TA’s Rule 11 (b) places a meaningful restriction on all of its employees and job applicants; in that sense the rule is one of general applicability and satisfies the equal protection principle without further inquiry. The District Court, however, interpreted the rule as applicable to the limited class of persons who regularly use narcotic drugs, including methadone. As so interpreted, we are necessarily confronted with the question whether the rule reflects an impermissible bias against a special class.
Respondents have never questioned the validity of a special rule for all users of narcotics. Rather, they originally contended that persons receiving methadone should not be covered by that rule; in other words, they should not be included within a class that is otherwise unobjectionable. Their constitutional claim was that methadone users are entitled to be treated like most other employees and applicants rather than like other users of narcotics. But the District Court’s findings unequivocally establish that there are relevant differences between persons using methadone regularly and persons who use no narcotics of any kind.32
*589Respondents no longer question the need, or at least the justification, for special rules for methadone users. Indeed, they vigorously defend the District Court’s opinion which expressly held that it would be permissible for TA to have a special rule denying methadone users any employment unless they had been undergoing treatment for at least a year, and another special rule denying even the most senior and reliable methadone users any of the more dangerous jobs in the system.
The constitutional defect in TA’s employment policies, according to the District Court, is not that TA has special rules for methadone users, but rather that some members of the class should have been exempted from some requirements of the special rules. Left intact by its holding are rules requiring special supervision of methadone users to detect evidence of drug abuse, and excluding them from high-risk employment. Accepting those rules, the District Court nonetheless concluded that employment in nonsensitive jobs could not be denied to methadone users who had progressed satisfactorily with their treatment for one year, and who, when examined individually, satisfied TA’s employment criteria. In short, having recognized that disparate treatment of methadone users simply because they are methadone users is permissible — and having excused TA from an across-the-board requirement of individual consideration of such persons — the District Court construed the Equal Protection Clause as requiring TA to adopt additional and more precise special rules for that special class.
*590But any special rule short of total exclusion that TA might adopt is likely to be less precise — and will assuredly be more costly33 — than the one that it currently enforces. If eligibility is marked at any intermediate point — whether after one year of treatment or later — the classification will inevitably discriminate between employees or applicants equally or *591almost equally apt to achieve full recovery.34 Even the District Court’s opinion did not rigidly specify one year as a constitutionally mandated measure of the period of treatment that guarantees full recovery from drug addiction.35 The uncertainties associated with the rehabilitation of heroin addicts precluded it from identifying any bright line marking the point at which the risk of regression ends.36 By contrast, the “no drugs” policy now enforced by TA is supported by the legitimate inference that as long as a treatment program (or other drug use) continues, a degree of uncertainty persists.37 Accordingly, an employment policy that postpones *592eligibility until the treatment program has been completed, rather than accepting an intermediate point on an uncertain line, is rational. It is neither unprincipled nor invidious in the sense that it implies disrespect for the excluded subclass.
At its simplest, the District Court’s conclusion was that TA’s rule is broader than necessary to exclude those methadone users who are not actually qualified to work for TA. We may assume not only that this conclusion is correct but also that it is probably unwise for a large employer like TA to rely on a general rule instead of individualized consideration of every job applicant. But these assumptions concern matters of personnel policy that do not implicate the principle safeguarded by the Equal Protection Clause.38 As the District Court recognized, the special classification created by TA’s rule serves the general objectives of safety and efficiency.39 Moreover, the exclusionary line challenged by respondents “is not one which is directed 'against’ any individual or category of persons, but rather it represents a policy choice . . . made by that branch of Government vested with the power to make such choices.” Marshall v. United States, 414 U. S. 417, 428. *593Because it does not circumscribe a class of persons characterized by some unpopular trait or affiliation, it does not create or reflect any special likelihood of bias on the part of the ruling majority.40 Under these circumstances, it is of no constitutipnal significance that the degree of rationality is not as great with respect to certain ill-defined subparts of the classification as it is with respect to the classification as a whole. Mathews v. Diaz, 426 U. S. 67, 83-84.41
*594No matter how unwise it may be for TA to refuse employment to individual car cleaners, track repairmen, or bus-drivers simply because they are receiving methadone treatment, the Constitution does not authorize a federal court to interfere in that policy decision. The judgment of the Court of Appeals is
Reversed.
This Court’s Rule 19 provides:
“Considerations governing review on certiorari
“1. A review on writ of certiorari is not a matter of right, but of sound judicial discretion, and will be granted only where there are special and important reasons therefor. The following, while neither controlling nor fully measuring the court’s discretion, indicate the character of reasons which wih be considered:
“(b) Where a court of appeals . . . has decided a federal question in a way in conflict with applicable decisions of this court; or has so far departed from the accepted and usual course of judicial proceedings, or so far sanctioned such a departure by a lower court, as to call for an exercise of this court’s power of supervision.”
Thus, about 13,400 employees are involved in the maintenance of subway cars, buses, track, tunnels, and structures. Another 5,600 work in subway stations, and over 2,000 are engaged in office tasks that include the handling of large sums of money. TA hires about 3,000 new employees each year.
By its terms, Rule 11 (b) does not apply to persons who formerly used methadone or any other drug, and the District Court did not find that TA had any general policy covering former users. On the contrary, the court found that “[t]he situation is not entirely clear with respect to the policy of the TA regarding persons who have successfully concluded participation in a methadone program.” 399 F. Supp., at 1036.
Although it did not settle the question of what policy TA enforces in this respect, the District Court included former users in the plaintiff class. It then afforded them relief from any blanket exclusionary policy that TA might enforce, although, again, the supporting factual findings were admittedly “not [based on] a great deal” of evidence. Id., at 1051.
TA contends that the meager evidence received at trial on the “former users” issue was insufficient to support either the class or relief determinations made with respect to those persons. We go further. As far as we are aware there was no evidence offered at trial, and certainly none relied upon by the District Court, that TA actually refused employment to any former user entitled to relief under the injunction ordered by that court. (As we point out in n. 12, infra, the one named plaintiff, Frasier, who was a former user when the complaint was filed was clearly a current user at the time he first applied for a job with TA and may well have been properly perceived as a current user when he next applied, notwithstanding his assertion of successful completion during the intervening three weeks. In any case, he had not completed a full year of methadone maintenance and could therefore be excluded under the District Court’s injunction.)
It follows that neither the' findings of fact, nor the record evidence, squarely presents any issue with respect to former users that must be *573resolved in order to dispose of this litigation. And, of course, it is those findings and that evidence, rather than statements of the parties on appeal and even offhand and clearly erroneous characterizations of the findings and evidence by the Court of Appeals, see opinion of MR. Justice Powell, post, at 594^595, that determine the issues properly before this Court. A policy excluding all former users would be harder to justify than a policy applicable only to persons currently receiving treatment. A court should not reach out to express an opinion on the constitutionality of such a policy unless necessary to adjudicate a concrete dispute between adverse litigants. We shall therefore confine our consideration to the legality of TA’s enforcement of its Rule 11 (b) against current users of methadone.
“Heroin is a narcotic which is generally injected into the bloodstream by a needle. It is a central nervous system depressant. The usual effect is to create a ‘high’ — euphoria, drowsiness — for about thirty minutes, which then tapers off over a period of about three or four hours. At the end of this time the heroin user experiences sickness and discomfort known as ‘withdrawal symptoms.’ There is intense craving for another shot of heroin, after which the cycle starts over again. A typical addict will inject heroin several times a day.” 399 F. Supp., at 1038.
The District Court found that detoxification is accomplished “by switching a heroin addict to methadone and gradually reducing the doses of methadone to zero over a period of about three weeks. The patient thus detoxified is drug free. Moreover, it is hoped that the program of gradually reduced doses of methadone leaves him without the withdrawal symptoms, or the ‘physical dependence’ on a narcotic.” Ibid.
“The five major public or semi-public methadone maintenance programs in New York City are:
“(1) The Beth Israel program . . . with 35 clinics treating 7100 patients;
“(2) A program administered by the City of New York with 39 clinics treating 12,400 patients (hereafter referred to as ‘the City program’);
“(3) A program administered by the Bronx State Hospital and the Albert Einstein College of Medicine, with 7 clinics treating about 2400 patients;
“ (4) A program operated by the Addiction Research and Treatment Center (ARTC) with 6 clinics treating about 1200 patients; and
“(5) A program operated by the New York State Drug Abuse Control Commission (DACC), with 8 clinics treating about 1100 patients.
“The total number of patients treated in public or semi-public programs is about 26,000. It appears that these programs are financed almost entirely by federal, state and city funds.” Id., at 1040.
“[V]ery little specific information was provided [at trial] regarding the private clinics.” Id., at 1046. What evidence there was indicated that those clinics were likely to be less successful and less able to provide accurate information about their clients than the public clinics. Id., at 1046, 1050.
Although the United States Food and Drug Administration has also issued regulations in this area, 21 CFR §§291.501, 291.505 (1978), the New York State regulations are as or more stringent and thus effectively-set the relevant standards for the authorized methadone maintenance programs involved in this case. Under those regulations, in-clinic ingestion of methadone must be observed by staff members, 14 NYCRR § 2021.13 (b) (1976), and must occur with a frequency of six days a week during the first three months, no less than three days a week thereafter through the second year of treatment, and two days a week thereafter. § 2021.13 (c) (1). Tests are required to prevent hoarding of take-home doses, excessive use of methadone, and illicit use of other drugs or alcohol, any of which, if found, can result in increased clinic-visit frequency or in separation from the program. §§2021.13 (c)(2), 2021.13 (g). The programs are also required to include “a comprehensive range of rehabilitative services on-site under professional supervision,” § 2021.13 (e), although participation in many of these services is voluntary and irregular.
“I conclude from all the evidence that the strong majority of methadone maintained persons are successful, at least after the initial period of adjustment, in keeping themselves free of the use of heroin, other illicit drugs, and problem drinking.” 399 F. Supp., at 1047.
Thus, for example:
“Dr. Trigg of Beth Israel testified that about 5,000 out of the 6,500-7,000 patients in his clinics have been on methadone maintenance for a year or more. He further testified that 75% of this 5,000 are free from illicit drug use.” Id., at 1046.
Similarly, although the figures may be somewhat higher for the city and Bronx State Hospital programs, only 70% of the ARTC patients with a year’s tenure or more were found to be free from illicit drug or alcohol use. It is reasonable to infer from this evidence that anywhere from 20% to 30% of those who have been on maintenance for over a year have drug or alcohol problems.
Respondent Beazer was dismissed in November 1971 when his heroin addiction became known to TA and shortly after he had enrolled in a methadone maintenance program; he successfully terminated his treatment in November 1973. Respondent Reyes began his methadone treatment in 1971 and was dismissed by TA in 1972. At the time of trial, in 1975, he was still participating in a methadone program.
Respondent Frasier was on methadone maintenance for only five months, from October 1972 until March 1973. TA refused to employ bim as a bus operator in March 1973 and as a bus cleaner in April 1973. Frasier did not participate in a methadone program for even half a year. Moreover, he tested positively for methadone use at the time of his March application and only a few weeks before his April application was rejected under Rule 11 (b). See 399 F. Supp., at 1034; App. 32A. Under these *577circumstances, the District Court’s characterization of Frasier as a “former” user at the time he applied, and its inclusion of Frasier in the group of “tenured” methadone users for whom it felt relief was appropriate under the Equal Protection Clause, see n. 32, infra, are without apparent justification.
Respondent Diaz entered a methadone maintenance program in December 1968 and was still receiving treatment at the time of trial. He was refused employment as a maintenance helper in 1970.
The District Court summarized the testimony concerning one of the largest and most successful public programs:
“The witnesses from the Beth Israel program testified that about one-third of the patients in that program, after a short period of adjustment, need very little more than the doses of methadone. The persons in this category are situated fairly satisfactorily with respect to matters such *578as family ties, education and jobs. Another one-third of the patients at Beth Israel need a moderate amount of rehabilitation service, including vocational assistance, for a period of several months or about a year. A person in this category may, for instance, have finished high school, but may have a long heroin history and no employment record. A final one-third of the patients at Beth Israel need intensive supportive services, are performing in the program marginally, and either will be discharged or will be on the brink of discharge.” 399 F. Supp., at 1048.
The Court of Appeals reversed the District Court on one issue relating to relief. The lower court had denied reinstatement and backpay relief to two of the four named plaintiffs because they admitted having violated TA’s unquestionably valid rule against taking heroin while being in TA’s employ. App. to Pet. for Cert. 77a-78a. The Court of Appeals reversed. It determined that the two plaintiffs’ former heroin use and violation of TA’s rules on that account were irrelevant because TA explicitly premised their firing exclusively on their use of methadone. 558 F. 2d, at 101.
Section 504 of the Rehabilitation Act, 87 Stat. 394, as set forth in 29 U. S. C. § 794, provides:
“No otherwise qualified handicapped individual in the United States, as defined in section 706 (6) of this title, shall, solely by reason of his handicap, be excluded from the participation in, be denied the benefits of, or be subjected to discrimination under any program or activity receiving Federal financial assistance.”
It is stipulated that the TA receives federal financial assistance.
In relevant part, § 7 (6) of the Act, 29 U. S. C. § 706 (6), as amended and redesignated, 92 Stat. 2984, 29 U. S.- C. § 706 (7) (B) (1976 ed., Supp. Ill), provides:
“[T]he term ‘handicapped individual’ . . . means any person who (i) has a physical or mental impairment which substantially limits one or more of such person’s major life activities, (ii) has a record of such an impairment, or (iii) is regarded as having such an impairment. For purposes of sections 503 and 504 as such sections relate to employment, such term does not include any individual who is an alcoholic or drug abuser whose current use of alcohol or drugs prevents such individual from performing the duties of the job in question or whose employment, by reason of such current alcohol or drug abuse, would constitute a direct threat to property or the safety of others.”
The question whether a cause of action on behalf of handicapped persons may be implied under § 504 of the Rehabilitation Act will be addressed by this Court in Southeastern Community College v. Davis, No. 78-711, cert. granted, 439 U. S. 1065.
The latest act of alleged discrimination cited in respondents’ complaint occurred in April 1973, while the Act was passed on September 26, 1973, Pub. L. 93-112, Title V, and the amendment to § 7 (6) went into effect on November 6, 1978.
See n. 17, supra.
In order for the District Court’s findings to bring the respondent class conclusively within the Act, we would have to find that denying employment to a methadone user because of that use amounts to excluding an “otherwise qualified handicapped individual . . . solely by reason of his handicap.” Among other issues, this would require us to determine (1) whether heroin addicts or current methadone users qualify as “handicapped individual [s]” — i. e., whether that addiction or use is (or is perceived as) a “physical . . . impairment which substantially limits one or more . . . major life activities”; (2) whether methadone use prevents the individual “from performing the duties of the job” or “would constitute a direct threat to property or the safety of others”; and (3) whether the members of the respondent class are “otherwise qualified” — the meaning of which phrase is at issue in Southeastern Community College v. Davis, supra.
See n. 1, supra, and accompanying text. Respondents may exaggerate the degree to which the recent amendment altered the law as it existed when we granted certiorari. Even before the Court of Appeals heard argument in this case, in fact, the Attorney General of the United States had issued an interpretation of the Act as it then existed which concluded that the Act “does in general prohibit discrimination against alcoholics and drug addicts in federally-assisted programs . . . .” Opinion of the Honorable Griffin B. Bell, Attorney General of the United States, to the Honorable Joseph A. Califano, Secretary, Department of Health, *582Education, and Welfare, Apr. 12, 1977. Respondents brought this interpretation to our attention before we granted certiorari. App. to Brief in Opposition A5-A6.
“From Hayburn’s Case, 2 Dall. 409, to Alma Motor Co. v. Timken-Detroit Axle Co.[, 329 U. S. 129,] and the Hatch Act case[, United Public Workers v. Mitchell, 330 U. S. 75,] decided this term, this Court has followed a policy of strict necessity in disposing of constitutional issues. The earliest exemplifications, too well known for repeating the history here, arose in the Court’s refusal to render advisory opinions and in applications of the related jurisdictional policy drawn from the case and controversy limitation. U. S. Const., Art. III....
“The policy, however, has not been limited to jurisdictional determinations. For, in addition, 'the Court [has] developed, for its own governance in the cases confessedly within its jurisdiction, a series of rules under which it has avoided passing upon a large part of all the constitutional questions pressed upon it for decision.’ Thus, as those rules were listed in support of the statement quoted, constitutional issues affecting legislation will not be determined in friendly, nonadversary proceedings; in advance of the necessity of deciding them; in broader terms than are required by the precise facts to which the ruling is to be applied; if the record presents some other ground upon which the case may be disposed of; at the instance of one who fails to show that he is injured by the statute’s operation, or who has availed himself of its benefits; or if a eon-*583struction of the statute is fairly possible by which the question may be avoided.” Rescue Army v. Municipal Court, 331 U. S. 549, 568-569 (footnotes omitted), quoting Ashwander v. TVA, 297 U. S. 288, 346 (Brandeis, J., concurring).
Respondents suggest that the lower courts properly reached the constitutional issue first because only under the Equal Protection Clause could all of the class members, including white methadone users (who presumably do not have standing in this case under Title VII or § 1981) obtain all of the relief including backpay, sought in their complaint. In addition, they point to TA’s argument that Title VII and § 1981 are unconstitutional insofar as they authorize relief against a state subdivision without any direct allegation or proof of intentional discrimination. Cf. Fitzpatrick v. Bitzer, 427 U. S. 445; National League of Cities v. Usery, 426 U. S. 833; Washington v. Davis, 426 U. S. 229; Fry v. United States, 421 U. S. 542; Katzenbach v. Morgan, 384 U. S. 641. Under this latter point, it is argued that the District Court quite properly decided to address the constitutionality of a municipal agency’s hiring practices before addressing the constitutionality of two Acts of Congress.
Whatever the theoretical validity of respondents’ explanations for the actions of the District Court' and the Court of Appeals, the fact remains that we are forced to speculate about what motivated them because they never explained their haste to address a naked constitutional issue despite the presence in the case of alternative statutory theories. It also bears noting that in its second opinion the District Court did decide that TA’s policy violated a federal statute, and its decision, without addressing any constitutional issue, provided a statutory basis for virtually all of the relief that it ultimately awarded. Had it confronted the issue, therefore, it presumably would have concluded that it could have decided the case without addressing the constitutional issue on which it initially decided the ease.
The failure of the Court of Appeals to address the statutory issue decided by the District Court does not, of course, prevent this Court from reaching the issue. Cf. University of California Regents v. Bakke, 438 U. S. 265. We conclude that it is appropriate to reach the issue in this case, rather than remand it to the Court of Appeals, because it was fully aired before the District Court, it involves the application of settled legal principles to uncontroversial facts, and it has been carefully briefed in *584this Court without any of the parties’ even suggesting the possibility of a remand.
Moreover, our treatment of the Title YII claim also disposes of the § 1981 claim without need of a remand. Although the exact applicability of that provision has not been decided by this Court, it seems clear that it affords no greater substantive protection than Title YII.
“Statistics are . . . competent in proving employment discrimination. We caution only that statistics are not irrefutable; they come in infinite variety and, like any other kind of evidence, they may be rebutted. In short, their usefulness depends on all the surrounding facts and circumstances.” Teamsters v. United States, 431 U. S. 324, 339-340 (footnote omitted).
From the time they filed their complaint until their submissions to this Court, respondents have relied on statistics to demonstrate the discriminatory effect of TA’s methadone policy. They have never attempted to present a discriminatory purpose case and would be hard pressed to do so in the face of the District Court’s explicit finding that no animus motivated TA in establishing its policy, 414 F. Supp. 277, 279 (SDNY 1976), and in the face of TA’s demonstration in forms filed with the Equal Employment Opportunity Commission that the percentage of blacks and Hispanics in its work force is well over twice that of the percentage in the work force in the New York metropolitan area.
Because of our conclusion on the merits of respondents’ Title VII claim, we need not address the constitutional challenge made by TA to Title VII insofar as it authorizes relief against a municipal agency under the circumstances of this case. See n. 23, supra.
Indeed, it is probable that none of the employees comprising this 81% were methadone users. The parties stipulated that:
“TA employees showing physical manifestations of drug abuse other than the definite presence of morphine or methadone or other illicit drug in the urine, are referred for consultation to [the medical director] . . . .” App. 86A (emphasis added).
In view of this stipulation and the District Court’s finding that few if any physical manifestations of drug abuse characterize methadone-maintained persons, 399 F. Supp., at 1042-1045, it seems likely that such persons would not be included in the statistical pool referred to by the District Court. It should also be noted that when the dissent refers to the rejection of almost 5% of all applicants “due to the rule,” post, at 600, the reference is to all narcotics users rather than to methadone users. The record does not tell us how many methadone users were rejected.
The statistic relied upon by the District Court was derived from a study of methadone patients prepared by a researcher at Rockefeller University based upon data supplied by the public methadone clinics in New York City. In that the District Court admittedly received virtually no evidence about the private clinics, their funding, and their participants, see n. 7, supra, there is no basis for assuming that the Rockefeller University statistic is applicable to participants in the private programs.
To demonstrate employability, the District Court referred to a study indicating that 34% to 59% of the methadone users who have been in a maintenance program for a substantial period of time are employed. The evidence was inconclusive with respect to all methadone users. 399 F. Supp., at 1047. However, the director of the second largest program in New York City testified that only 33% of the entire methadone-patient population in that program were employable. Tr. 345 (Jan. 10, 1975). On the statistics relating to illicit use of drugs and alcohol, see supra, at 575-576.
Although “a statistical showing of disproportionate impact [need not] always be based on an analysis of the characteristics of actual applicants,” Dothard v. Rawlinson, 433 U. S. 321, 330, “evidence showing that the figures for the general population might not accurately reflect the pool of qualified job applicants” undermines the significance of such figures. Teamsters v. United States, supra, at 340 n. 20.
If all of the participants in private clinics are white, for example, then only about 40% of all methadone users would be black or Hispanic — -compared to the 36.3% of the total population of New York City that was black or Hispanic as of the 1970 census. Assuming instead that the percentage of those minorities in the private programs duplicates their percentage in the population of New York City, the figures would still only show that 50% of all methadone users are black or Hispanic compared to 36.3% of the population in the metropolitan area. (The 20% figure relied upon by the dissent refers to blacks and Hispanics in the work force, rather than in the total population of the New York City metropolitan area. The reason the total-population figure is the appropriate one is because the 63% figure *587relied upon by respondents refers to methadone users in the population generally and not just those in the work force.)
Respondents recognize, and the findings of the District Court establish, that TA’s legitimate employment goals of safety and efficiency require the exclusion of all users of illegal narcotics, barbiturates, and amphetamines, and of a majority of all methadone users. See n. 4, supra; supra, at 575-576, and nn. 9-10; 577, and n. 14; n. 28, supra. The District Court also held that those goals require the exclusion of all methadone users from the 25% of its positions that are “safety sensitive.” See supra, at 578. Finally, the District Court noted that those goals are significantly served by — even if they do not require — TA’s rule as it applies to all methadone users including those who are seeking employment in non-safety-sensitive positions. See nn. 33, 37, infra. The record thus demonstrates that TA’s rule bears a “manifest relationship to the employment in question.” Griggs v. Duke Power Co., 401 U. S. 424, 432. See Albemarle Paper Co. v. Moody, 422 U. S. 405, 425. Whether or not respondents’ weak showing was sufficient to establish a prima facie case, it clearly failed to carry respondents’ ultimate burden of proving a violation of Title VII.
The District Court found that methadone is a narcotic. See 399 E. Supp., at 1038. See also id,., at 1044 (“The evidence is that, during the time patients are being brought up to their constant dosage of methadone (a period of about six weeks), there may be complaints of drowsiness, insomnia, excess sweating, constipation, and perhaps some other symptoms”). Moreover, every member of the class of methadone users was formerly addicted to the use of heroin. None is completely cured; otherwise, there would be no continuing need for treatment. All require some measure of special supervision, and all must structure their weekly routines around mandatory appearances at methadone clinics. The clinics make periodic cheeks as long as the treatment continues in order to detect evidence of drug abuse. Employers must review, and sometimes verify, these checks; since the record indicates that the information supplied by treatment centers is not uniformly reliable, see n. 7, supra, the employer *589has a special and continuing responsibility to review the condition of these persons.
In addition, a substantial percentage of persons taking methadone will not successfully complete the treatment program. The findings do not indicate with any precision the number who drop out, or the number who can fairly be classified as unemployable, but the evidence indicates that it may well be a majority of those taking methadone at any given time. See nn. 14 and 28, supra.
The District Court identified several significant screening procedures that TA would have to adopt specially for methadone users if it abandoned its rule. For example, the court noted that current methadone users (but no other applicants) would have to
“demonstrate that they have been on a reliable methadone program for a year or more; that they have faithfully abided by the rules of the program; [and] that, according to systematic tests and observations, they have been free of any illicit drug or alcohol abuse for the entire period of treatment, excluding a possible adjustment period . . . .” 399 F. Supp., at 1049.
The District Court also recognized that verifying the above demonstrations by the methadone user would require special efforts to obtain reliable information from, and about, each of the many different methadone maintenance clinics — a task that it recognized could be problematic in some cases. Id., at 1050; see n. 7, supra. Furthermore, once it hired a methadone user, TA would have a continuing duty to monitor his progress in the maintenance program and would have to take special precautions against his promotion to any of the safety-sensitive positions from which the District Court held he may be excluded.
The dissent is therefore repeatedly mistaken in attributing to the District Court a finding that TA’s “normal screening process without additional effort” would suffice in the absence of the “no drugs” rule. Post, at 608. See post, at 608 n. 14. Aggravating this erroneous factual assumption is a mistaken legal proposition advanced by the dissent — that TA can be faulted for failing to prove the unemployability of “successfully maintained methadone users. Post, at 605. Aside from the misallocation of the burden of proof that underlies this argument, it is important to note, see post, at 606, that TA did prove that 20% to 30% of the class afforded relief by the District Court are not “successfully maintained,” and hence are assuredly not employable. Even assuming therefore that the percentage of employable persons in the remaining 70% is the same as that in the class of TA applicants who do not use methadone, it is respondents who must be faulted for failing to prove that the offending 30% could be excluded as cheaply and effectively in the absence of the rule.
It may well be, in fact, that many methadone users who have been in programs for something less than a year are actually more qualified for employment than many others who have been in a program for longer than a year.
“The TA is not prevented from making reasonable rules and regulations about methadone maintained persons — such as requiring satisfactory performance in a program for a period of time such as a year . . . .” 399 F. Supp., at 1058.
These uncertainties are evident not only in the District Court’s findings but also in legislative consideration of the problem. See Marshall v. United States, 414 U. S. 417, 425-427.
The completion of the program also marks the point at which the employee or applicant considers himself cured of drug dependence. Moreover, it is the point at which the employee/applicant no longer must make regular visits to a methadone clinic, no longer has access to free methadone that might be hoarded and taken in excessive and physically disruptive doses, and at which a simple urine test — as opposed to a urine test followed up by efforts to verify the bona fides of the subject’s participation in a methadone program, and of the program itself — suffices to prove compliance with TA’s rules.
Respondents argue that the validity of these considerations is belied by TA’s treatment of alcoholics. Although TA refuses to hire new employees with drinking problems, it continues in its employ a large number of persons who have either been found drinking on the job or have been deemed unfit for duty because of prior drinking. These situations give rise to discipline but are handled on an individual basis. But the fact that TA has the resources to expend on one class of problem employees *592does not by itself establish a constitutional duty on its part to come up with resources to spend on all classes of problem employees.
The District Court also concluded that TA’s rule violates the Due Process Clause because it creates an “irrebuttable presumption” of unem-ployability on the part of methadone users. 399 F. Supp., at 1057. Respondents do not rely on the due process argument in this Court, and we find no merit in it.
“ [L] egislative classifications are valid unless they bear no rational relationship to the State’s objectives. Massachusetts Bd. of Retirement v. Murgia, [427 U. S. 307, 314]. State legislation ‘does not violate the Equal Protection Clause merely because the classifications [it makes] are imperfect.’ Dandridge v. Williams, 397 U. S. 471, 485.” Washington v. Yakima Indian Nation, 439 U. S. 463, 501-502. See also Vance v. Bradley, ante, at 108, quoting Phillips Chemical Co. v. Dumas School District, 361 U. S. 376, 385 (“Even if the classification involved here is to some extent both underinclusive and overinelusive, and hence the line drawn by Congress imperfect, it is nevertheless the rule that in a case like this 'perfection is by no means required’ ”).
Since Barbier v. Connolly, 113 U. S. 27, the Court’s equal protection cases have recognized a distinction between “invidious discrimination,” id., at 30 — i. e., classifications drawn “with an evil eye and an unequal hand” or motivated by “a feeling of antipathy” against, a specific group of residents, Yick Wo v. Hopkins, 118 U. S. 356, 373-374; Soon Hing v. Crowley, 113 U. S. 703, 710; see also Quong Wing v. Kirkendall, 223 U. S. 59; Holden v. Hardy, 169 U. S. 366, 398 — and those special rules that “are often necessary for general benefits [such as] supplying water, preventing fires, lighting districts, cleaning streets, opening parks, and many other objects.” Barbier, supra, at 31. See also Washington v. Davis, 426 U S. 229, 239-241. Quite plainly, TA’s Rule 11 (b) was motivated by TA’s interest in operating a safe and efficient transportation system rather than by any special animus against a specific group of persons. Cf. 414 F. Supp., at 279. Respondents recognize this valid general motivation, as did the District Court, and for that reason neither challenges TA’s rule as it applies to all narcotic user’s, or even to all methadone users. Because respondents merely challenge the rule insofar as it applies to some methadone users, that challenge does not even raise the question whether the rule falls on the “invidious” side of the Barbier distinction. Accordingly, there is nothing to give rise to a presumption of illegality and to warrant our especially “attentive judgment.” Cf. Truax v. Corrigan, 257 U. S. 312, 327.
“When a legal distinction is determined, as no one doubts that it may be, between night and day, childhood and maturity, or any other extremes, a point has to be fixed or a line has to be drawn, or gradually picked out by successive decisions, to mark where the change takes place. Looked at by itself without regard to the necessity behind it the line or point seems arbitrary. It might as well or nearly as well be a little more to one side or the other. But when it is seen that a line or point there must be, and that there is no mathematical or logical way of fixing it precisely, the decision of the legislature must be accepted unless we can say that it is very wide of any reasonable mark.” Louisville Gas Co. v. Coleman, 277 U. S. 32, 41 (Holmes, J., dissenting).