Opinion
BROUSSARD, J.
The issue before us is whether a hospital may permit clinical psychologists to take primary responsibility for the diagnosis and treatment of their hospitalized patients. Prior to 1978, regulations of the Department of Health Services (hereafter Department) declared that a psychiatrist must take charge of the diagnosis and treatment of all patients admitted to psychiatric wards or hospitals.1 In 1978, however, the Legislature enacted Health and Safety Code section 1316.5,2 which after confirming that hospitals could admit psychologists to their staffs, provided that such psychologists may, subject to the rules of the hospital, “carry professional responsibilities consistent with the scope of their licensure and competence.” In 1980 the Legislature added language declaring that if such a hospital offered services that both physicians and psychologists could perform, “such service may be performed by either, without discrimination.”
When the Department in 1983 reissued its 1975 regulations prohibiting hospitals from permitting a psychologist to carry primary responsibility for the diagnosis and treatment of patients, plaintiffs sued for declaratory relief. The trial court granted their motion for summary judgment, declared the regulations invalid, and directed the Department to issue new regulations permitting psychologists to take primary responsibility for the diagnosis and treatment of hospitalized patients. After a complex procedural history, recounted later in this opinion, the Court of Appeal reversed the trial court. [7]*7We granted review, and now uphold the ruling of the trial court, which we believe conforms to the language and carries out the purpose of the 1978 and 1980 legislation.
I. Background and History of This Litigation
Following the enactment of section 1316.5 in 1978, and its amendment in 1980, the Department considered amending its regulations to permit clinical psychologists to be responsible for the diagnosis and treatment of their patients. After public hearings, however, the Department on January 6, 1983, adopted regulations which provided that for patients admitted to psychiatric wards or hospitals, “[a] psychiatrist shall be responsible for the diagnostic formulation for each patient and the development and implementation of the individual patient’s treatment plan.” (Cal. Code Regs., tit. 22, §§ 70577, subd. (d)(1) and 71203, subd. (a)(1)(A), italics added.) These regulations are essentially the same as those in effect before the enactment and amendment of section 1316.5.
Plaintiffs, the California Association of Psychology Providers (CAPP) and several individual clinical psychologists, brought suit against the Department, the Department of Finance, and their directors. The complaint asserted seven causes of action. The first simply set out the facts recited previously in this opinion. The second cause of action sought mandamus on the theory that the regulations conflict with the statute. The third sought mandamus on the theory that the regulations were adopted in violation of the public hearing requirements of Government Code section 11346.8. The fourth, fifth and sixth causes of action sought injunctive relief. The seventh cause of action requested a declaration of plaintiffs’ rights with respect to the hallenged regulations.3
Plaintiffs moved for summary judgment on the seventh cause of action. The trial court granted the motion, and entered a judgment declaring that under section 1316.5, “clinical psychologists on the medical staff of a health facility are authorized to independently provide psychological services within the legal scope of their licensure, without physician supervision and without discriminatory restrictions. The provision of psychological services includes ultimate responsibility for the psychological care of hospitalized [8]*8patients and authority to admit and discharge patients provided that a physician shall be responsible for the necessary medical care of patients including completion of a physical examination upon admission of each patient.” The court held regulations 70577, subdivision (d)(1) and 71203, subdivision (a)(1)(A) invalid, and ordered the Department to adopt the regulations originally proposed in 1982.4
The Department announced that it would not appeal the trial court order and, about a month after the oral statement of decision (and before the filing of the written judgment), adopted the regulations as directed by the court. The California Hospital Association, the California Medical Association, and the California Psychiatric Association, joined by individual doctors, moved to vacate the judgment. The trial court denied the motion for want of standing, and the moving parties appealed.
Plaintiffs moved to dismiss the appeal, contending that appellants were not properly parties to the action and that the Department’s adoption of new regulations rendered the matter moot. The Court of Appeal granted the motion. In an order dated October 16, 1986, we granted appellants’ petition for review and retransferred the case to the Court of Appeal with directions to vacate the order of dismissal.
Upon retransfer, the Court of Appeal ruled sua sponte that the trial court judgment was not appealable. On November 25, 1987, we again granted review and retransferred, directing the Court of Appeal to vacate its dismissal and to hear the appeal on its merits.
Pursuant to our order, the Court of Appeal addressed the merits of the appeal and reversed the judgment below. It held that the Legislature intended clinical psychologists to have the right to diagnose and treat their hospitalized patients without supervision from a physician “only in those instances where a physician has initially ruled out a medical basis for the patient’s mental disorder and determined that it is not subject to medical treatment, and where the patient’s mental disorder does not subsequently become susceptible to medical treatment after admission to the health facili[9]*9ty.” The statutory prohibition against discrimination, it said, prohibits requiring supervision by a psychiatrist, but only “after a medical diagnosis and medical treatment have been ruled out. . . .” We granted review and retained the. case for decision.
II. Preliminary Procedural Issues
Our prior orders necessarily determined that the trial court ruling was appealable, that appellants have standing to appeal, and that the matter has not become moot. Those rulings are controlling under the doctrine of law of the case. (See Pigeon Point Ranch, Inc. v. Perot (1963) 59 Cal.2d 227, 230-232 [28 Cal.Rptr. 865, 379 P.2d 321].) Nevertheless, because our minute orders did not set out the reasoning of the court, and cannot serve as precedent to guide future decisions, we believe it appropriate to explain the basis for our decisions.
(a) Appealability.
The trial court entered summary judgment only as to plaintiffs’ seventh cause of action. The Court of Appeal originally concluded that because the judgment did not address plaintiffs’ other six asserted causes of action, appeal was barred by the one final judgment rule. (Code Civ. Proc., § 904.1.) Plaintiffs’ seventh cause of action, however, sought a declaration of plaintiffs’ rights with respect to the facts alleged in all other causes of action. The resulting judgment effectively disposed of the case. Once the trial court had determined that the existing regulations were invalid, and directed the Department to adopt new regulations, there would be no purpose in conducting further proceedings to decide whether to compel the same result by writs of injunction or mandamus. A judgment that leaves no issue to be determined except the fact of compliance with its terms is appealable. (Agricultural Labor Relations Bd. v. Tex-Cal Land Management, Inc. (1987) 43 Cal.3d 696, 702 [238 Cal.Rptr. 780, 739 P.2d 140]; Lyon v. Goss (1942) 19 Cal.2d 659, 669-670 [123 P.2d 11]; see Etienne v. DKM Enterprises (1982) 136 Cal.App.3d 487, 489 [186 Cal.Rptr. 321].)
(b) Standing to Appeal.
“ ‘Any aggrieved party’ may appeal from an adverse judgment. . . . [O]ne who is legally ‘aggrieved’ by a judgment may become a party of record and obtain a right to appeal by moving to vacate the judgment pursuant to Code of Civil Procedure section 663.” (County of Alameda v. Carlson (1971) 5 Cal.3d 730, 736 [97 Cal.Rptr. 385, 488 P.2d 953].) Appellants having filed such a motion, the only question is whether they qualify as persons aggrieved by the judgment.
[10]*10The issue is clear as to appellant California Hospital Association since the trial court directed the Department to issue regulations binding its member hospitals. The matter is less clear as to appellants California Medical Association, California Psychiatric Association, and the individual physicians. They are not directly regulated. The trial court’s judgment, however, diminishes the sphere of responsibility of physicians, particularly psychiatrists, vis-a-vis clinical psychologists, and thus can be expected to affect the authority and income of the physicians.
A review of prior cases indicates that this interest is sufficient to confer standing to appeal. (See County of Alameda v. Carlson, supra, 5 Cal.3d 730, which held that the California Welfare Rights Organization was aggrieved by a declaratory judgment striking down regulations that broadened eligibility for welfare grants; Simac Design, Inc. v. Alciati (1979) 92 Cal.App.3d 146 [154 Cal.Rptr. 676], which held supporters of a growth control initiative were aggrieved by a decision mandating issuance of building permits contrary to the terms of the initiative; Redevelopment Agency v. City of Berkeley (1978) 80 Cal.App.3d 158 [143 Cal.Rptr. 633], which held a homeowners group aggrieved by a judgment invalidating an initiative that removed their homes from a redevelopment plan.) We believe appellant physicians and psychiatrists have an interest adversely affected by the judgment (see Estate of Colton (1912) 164 Cal. 1, 5 [127 P. 643]) comparable to appellants in these cases.
(c) Mootness.
Plaintiffs contended that the case became moot when the Department complied with the trial court’s order and adopted new regulations. But the Department did not adopt those regulations as a result of ordinary administrative proceedings, but instead in response to the trial court’s judgment. So long as that judgment is in effect, the Department is not free to reconsider the regulations in question. We cannot assume that the Department would adopt the same regulations if the judgment were overturned.
The present case is thus comparable to County of Alameda v. Carlson, supra, 5 Cal.3d 730, in which the trial court rendered a judgment invalidating regulations that expanded eligibility for welfare grants and the Department of Social Welfare then adopted an emergency regulation narrowing eligibility. We held that an organization representing welfare recipients could appeal from the trial court order, and decided the case on the merits.
III. Diagnosis and Treatment of Hospitalized Patients
The Department’s 1983 regulations, by providing that a psychiatrist must be responsible for diagnosis and treatment of all mental patients, prohibited [11]*11a hospital from permitting a clinical psychologist to take responsibility for diagnosis and treatment of his own patients. The Court of Appeal opinion went halfway, permitting the psychologist to exercise that responsibility only after a physician has ruled out a medical cause for the patient’s condition or medical treatment of that condition. We explain that neither the Department’s regulations nor the limitations in the Court of Appeal opinion conforms to the language of section 1316.5.
(а) The Scope of Review.
When a court inquires into the validity of an administrative regulation to determine whether its adoption was an abuse of discretion, the scope of review is limited. As we said in Pitts v. Perluss (1962) 58 Cal.2d 824 [27 Cal.Rptr. 19, 377 P.2d 83], “[a]s to quasi-legislative acts of administrative agencies, ‘judicial review is limited to an examination of the proceedings before the officer to determine whether his action has been arbitrary, capricious, or entirely lacking in evidentiary support, or whether he has failed to follow the procedure and give the notices required by law.’ ” (P. 833; see Culligan Water Conditioning v. State Bd. of Equalization (1976) 17 Cal.3d 86, 92-93 [130 Cal.Rptr. 321, 550 P.2d 593].)5 When, however, a regulation is challenged as inconsistent with the terms or intent of the authorizing statute, the standard of review is different, because the courts are the ultimate arbiters of the construction of a statute. Thus, Morris v. Williams (1967) 67 Cal.2d 733 [63 Cal.Rptr. 689, 433 P.2d 697], in finding that the challenged regulations contravened legislative intent, rejected the agency’s claim that the only issue for review was whether the regulations were arbitrary or capricious. Our opinion explained that “[w]hile the construction of a statute by officials charged with its administration ... is entitled to great weight, nevertheless, ‘[wjhatever the force of administrative construction . . . final responsibility for the interpretation of the law rests with the courts.’ [Citation.] Administrative regulations that alter or amend the statute or enlarge or impair its scope are void and courts not only may, but it is their obligation to strike down such regulations.” (P. 748; see Dyna-Med, Inc. v. Fair Employment & Housing Com. (1987) 43 Cal.3d 1379, 1388-1389 [241 Cal.Rptr. 67, 743 P.2d 1323]; Hittle v. Santa Barbara County Employees Retirement Assn. (1985) 39 Cal.3d 374, 387 [216 Cal.Rptr. 733, 703 P.2d 73].) Although in determining whether the regulations are reasonably necessary to effectuate the statutory purpose we will not intervene in the absence of an arbitrary or capricious decision, “we need not [12]*12make such a determination if the regulations transgress statutory power.” (67 Cal.2d at p. 749.)
(b) The Plain Meaning of Section 1316.5.
Section 1316.5, subdivision (a), provides in relevant part:
“The rules of a health facility may enable the appointment of clinical psychologists on such terms and conditions as the facility shall establish. In such health facilities, clinical psychologists may hold membership and serve on committees of the medical staff and carry professional responsibilities consistent with the scope of their licensure and their competence, subject to the rules of the health facility.
“. . . If a health service is offered by a health facility with both licensed physicians and surgeons and clinical psychologists on the medical staff, which both licensed physicians and surgeons and clinical psychologists are authorized by law to perform, such service may be performed by either, without discrimination . . . .”6
The meaning of section 1316.5 is reasonably clear on its face. The first sentence permits a hospital to appoint clinical psychologists to its staff on such terms and conditions as it chooses. The next sentence provides that psychologists so admitted may, subject to the rules of the hospital, “carry professional responsibilities consistent with the scope of their licensure . . . .” The scope of that licensure is defined by the Psychologist Licensing Law, Business and Professions Code section 2903; it includes “diagnosis, prevention, treatment and amelioration of psychological problems and emotional disorders of individuals and groups.” The only statutory limitation is that psychologists cannot prescribe drugs, perform surgery, or administer electroconvulsive therapy. (Bus. & Prof. Code, § 2904.)
Does this section, by giving the psychologist authority to diagnose and treat psychological disorders, also confer primary responsibility for the diagnosis and treatment? The answer is apparent not only from the language but from the history and purpose of Business and Professions Code section 2903. This section antedates section 1316.5, and thus was drafted primarily to regulate outpatient practice, and in that setting the responsibility of the psychologist is obvious. When a patient comes to a psychologist’s office, the psychologist must decide whether to take the case. This necessarily involves the responsibility to consider the full range of possible causes of the patient’s illness, select the appropriate treatment methods, and if treat[13]*13ment involves a method beyond his authority or competence, refer the patient to someone else. If the psychologist retains the case, he or she necessarily has primary responsibility for the diagnosis and treatment—no other professional is even involved. Appellants concede this to be true for outpatient treatment, contending only that things are different in a hospital. But neither section 1316.5 nor Business and Professions Code section 2903 distinguishes between hospital and outpatient practice. It would radically rewrite the statutes for us to hold that they confer primary responsibility for diagnosis and treatment in an outpatient setting but that in a hospital the psychologist may diagnose and treat only if someone else assumes primary responsibility for such acts.
In short, under Business and Professions Code section 2903 psychologists are licensed to diagnose and treat psychological problems of individual patients, and under section 1316.5 they may carry responsibilities in hospitals within the scope of their license. It follows that psychologists may carry the responsibility of diagnosing and treating the psychological problems of patients in hospitals.7
The second paragraph of section 1316.5 is equally clear. It provides that if a hospital has both physicians and psychologists on its staff, and offers a service that both are “authorized by law to perform, such service may be performed by either, without discrimination.” The only service both physicians and psychologists are authorized by law to perform is the diagnosis and treatment of psychological and emotional disorders, without use of drugs, surgery, or electroconvulsive therapy. The “without discrimination” clause signifies that in performing such services the two professions, each authorized by law, stand on an equal footing; neither is subject to constraints from which the other is free. Under the 1983 regulations, however, a psychiatrist may perform such services for his or her hospitalized patient if the psychiatrist believes them necessary, without referral, approval, or supervision from anyone else. A psychologist, however, can treat his or her patient only if a psychiatrist decides the services are necessary, decides not to perform them himself, and selects this particular psychologist from among the psychologists and psychiatrists available. Moreover, in performing those services, the psychologist remains subject to the supervision of the psychiatrist,8 who retains the authority to change the treatment plan and [14]*14terminate the psychologist’s participation. Thus the 1983 regulations compel the discrimination the statute forbids.
We conclude that section 1316.5 means what the trial court said it meant: that a hospital may permit clinical psychologists on its staff to “provide psychological services within the legal scope of their licensure, without physician supervision and without discriminatory restrictions.”
(c) The Legislative History of Section 1316.5.
Appellants’ principal argument is that, notwithstanding the wording of section 1316.5, the legislative history of the 1978 and 1980 enactments shows that the Legislature did not intend to permit hospitals to allow psychologists to assume primary responsibility for diagnosis and treatment. Appellants point out that when Senate Bill No. 259 was originally introduced in 1978, it contained a subdivision (c) which said that if a patient was admitted by a clinical psychologist, the facility shall designate a physician to provide for medical needs, but that “the patient’s care, other than medical care, shall be the responsibility and subject to the direction of the psychologist.” The Department advised the Legislature that this language might conflict with Medicare and Medicaid (Medi-Cal) regulations, which then provided that a patient could be “admitted to a hospital only on the recommendation of a physician.” (42 C.F.R., former § 405.102(h)(1).)* 9 The California Medical Association (CMA) also objected to the provisions authorizing psychologists to admit patients and giving them responsibility for treatment. The subdivision was subsequently deleted, and the Department then reported to the Governor that the amended version averted opposition from the CMA.
Likewise, Senate Bill No. 1443 in 1980 originally proposed to amend section 1316.5 to provide explicitly that clinical psychologists be allowed “to admit and treat patients within the scope of their licensure, without a physician and surgeon ordering the care.” The Department again advised the Legislature that this language might jeopardize federal funding, and the CMA again noted its opposition to the language on admission and treatment. The Legislature then deleted the quoted language, replacing it with a general prohibition against discrimination.
[15]*15Finally, the dissent emphasizes that the 1983 Legislature defeated Senate Bill No. 181, which, in language virtually identical to the trial court’s order, would have provided that “clinical psychologists . . . shall be responsible, within the scope of their licensure, for diagnostic formulations and the development and implementation of individual treatment plans . . . .” On the other hand, after the Department adopted regulations conforming to the trial court’s order, the 1986 Legislature rejected Assembly Bill No. 3592 which would have overturned that order and restored the prior law. We note the parallel language of that bill and the Department’s 1983 regulations:
Assembly Bill No. 3592 “A psychiatrist shall be responsible for the diagnostic formulation and the development and implementation of the treatment plan.”
1983 regulations “A psychiatrist shall be responsible for the diagnostic formulation for each patient and the development and implementation of the individual patient’s treatment plan.”
Appellants conclude from the Legislature’s removal of specific language relating to diagnosis and treatment from the 1978 and 1980 legislation, and the defeat of the 1983 bill, that the Legislature did not intend to permit psychologists to diagnose and treat patients without psychiatric supervision. The defeat of the 1986 legislation, however, suggests the contrary conclusion. A number of other considerations also lead us to reject appellants’ theory of legislative intent.
First, in attempting to ascertain the legislative intent, the most significant source is the Legislature’s own declaration of findings and purpose that accompanied the 1978 legislation. It stated in relevant part: “The interests of the people of this state demand that all appropriate resources, including inpatient facilities, be available to assist in the diagnosis, prevention, treatment, and amelioration of psychological problems and emotional and mental disorders. However, a branch of healing arts predominately concerned with such afflictions, psychology, is under present law, unduly restricted in its access to, and utilization of, health facilities. As a result, many patients under the care of a psychologist, when admitted to a hospital, cannot continue to receive care from the therapist of their choice . . . . [fl] The Legislature further finds and declares that psychology is an independent health profession, as set forth and prescribed in the Psychology Licensing Law. The role of the psychologist as primary provider of mental health care has been repeatedly recognized at both the state and federal levels of government. In the institutional setting, psychologists play a vital role in the [16]*16clinical operation and program direction of the state hospitals, and county Short-Doyle programs, [fl] It is therefore the intent of the Legislature, in enacting this act, to authorize health facilities on local determination to make inpatient care available for psychological patients and to expand staff and professional services that may be offered by health facilities to include licensed psychologists having appropriate training and clinical experience.”
According to this declaration the Legislature wanted to change “present law,” because that law restricted the utilization of psychologists in “inpatient facilities,” i.e., in hospitals. Since no statute then or now restricted the use of psychologists in hospitals, the Legislature’s reference to “present law” must have referred to the Department’s regulations requiring that a psychiatrist supervise diagnosis and treatment of all persons hospitalized for mental illness. We conclude that the Legislature intended to bring about a change in those regulations.
Moreover, the Legislature identified a particular problem that required correction—that many hospitalized patients could not continue to receive care from their psychologist. The Department’s regulations required the hospital to give primary responsibility to a physician with whom the patient may have had no previous relationship—a physician who would have the authority to decide that the patient should not receive treatment from the psychologist. Thus, we again may infer an intent to alter the existing regulations.
The legislative declaration that “psychology is an independent health care profession,” and its recognition of the psychologist “as primary provider of mental health care” seem designed to put the two professions—psychology and medicine—on as equal a level as possible within the scope of their respective licensures. The 1980 amendment, providing that where both professions have authority either may perform “without discrimination,” confirms this conclusion. The Department’s regulations, however, establish a hospital hierarchy under which physicians outrank psychologists as to those functions for which both are licensed and qualified.
Second, after the 1978 bill was enacted, Senator Carpenter requested an interpretation of its language. The Legislative Counsel responded in a written opinion that under section 1316.5, a hospital “will be authorized to permit admission of patients upon the referral of a clinical psychologist. . . [who may] treat a patient within the scope of his or her licensure without a physician and surgeon ordering the care.” (Ops. Cal. Legis. Counsel, No. 16615 (Jan. 4, 1979) Psychologists’ Use of Health Facilities.) A subsequent unpublished opinion of the Attorney General agreed. (Cal. Atty. Gen., [17]*17Letter to Sen. Paul B. Carpenter re: Opinion of Cal. Legis. Counsel, No. 16615 (Mar. 15, 1979).)
When the 1980 Legislature considered amending section 1316.5, it presumably had before it the opinions of the Legislative Counsel and of the Attorney General. If those opinions misconstrued the law, here was the opportunity to correct matters. But the Legislature left intact the language construed by the Legislative Counsel and by the Attorney General, and added language prohibiting discrimination against psychologists practicing within the scope of their licensure.
“Opinions of the Attorney General, while not binding, are entitled to great weight. [Citations.] In the absence of controlling authority, these opinions are persuasive ‘since the Legislature is presumed to be cognizant of that construction of the statute.’ ” (Napa Valley Educators’ Assn. v. Napa Valley Unified School Dist. (1987) 194 Cal.App.3d 243, 251 [239 Cal.Rptr. 395].) In Meyer v. Board of Trustees (1961) 195 Cal.App.2d 420 [15 Cal.Rptr. 717], the court found the Attorney General’s construction of the teacher tenure requirements was decisive of the case, noting that “[a]s a contemporaneous construction, and because he was charged with the duty of rendering an opinion with respect to its meaning, the interpretation of the subject statute by the attorney general in 1936 is entitled to great respect. [Citations.] [U] It must be presumed that the aforesaid interpretation has come to the attention of the Legislature, and if it were contrary to the legislative intent that some corrective measure would have been adopted . . . .” (Pp. 431-432.) Again in Ventura v. City of San Jose (1984) 151 Cal.App.3d 1076, 1080 [199 Cal.Rptr. 216], the court relied heavily on an Attorney General opinion concerning the preemptive effect of state fireworks regulation, stating that “We can presume that this five-year-old opinion has come to the attention of the Legislature, and that if it were a misstatement of the legislative intent, ‘some corrective measure would have been adopted.’”
While we have found no cases extending that rule to constructions by the Legislative Counsel, the logic is the same. Indeed the rule is particularly compelling as to opinions of the Legislative Counsel, since they are prepared to assist the Legislature in its consideration of pending legislation.
Third, the rule of construction on which appellants rely is inapplicable to the present case. They assert that “[t]he rejection by the Legislature of a specific provision contained in an act as originally introduced is most persuasive to the conclusion that the act should not be construed to include the omitted provision.” (Rich v. State Board of Optometry (1965) 235 Cal.App.2d 591, 607 [45 Cal.Rptr. 512].) That principle, however, cannot [18]*18apply if the specific language is replaced by general language that includes the specific instance. If, for example, a bill were introduced to prohibit discrimination against “diabetics,” then amended to prohibit discrimination “on the basis of medical condition,” the deletion of the reference to diabetics would not exclude them from the protection of the act. Or if a bill were introduced dealing with “teachers’ salaries in Los Angeles County,” then amended to deal with “teachers’ salaries” generally, we would not construe it to apply to all counties except Los Angeles.
In the present case, the language adopted by the Legislature— “scope of licensure” (1978 law) and “authorized by law to perform” (1980 law)—includes the authority to diagnose and treat patients, so we cannot infer an intent to exclude authority to perform such acts. And the 1980 provision barring “discrimination” against either profession would clearly prohibit a rule that members of one profession have supervisory authority over the other, so we cannot infer an intent to permit such practices.
Finally, it is well settled “that in attempting to ascertain the legislative intention effect should be given, whenever possible, to the statute as a whole and to every word and clause thereof, leaving no part of the provision useless or deprived of meaning.” (Weber v. County of Santa Barbara (1940) 15 Cal.2d 82, 86 [98 P.2d 492]; Gay Law Students Assn. v. Pacific Tel. & Tel. Co. (1979) 24 Cal.3d 458, 478 [156 Cal.Rptr. 14, 595 P.2d 592].) Appellants seek to exclude any statutory interpretation that would give psychologists authority to diagnose and treat hospital patients comparable to their authority over outpatients, but offer no alternative interpretation that would give any significance or role to most of the statutory language. Yet the 1978 and 1980 enactments were intended to do more than simply authorize hospitals to admit clinical psychologists to their staffs; the first sentence of the 1978 law would have sufficed for that purpose. The additional provision authorizing psychologists to carry professional responsibilities consistent with their licensure would lack significance if they may only carry such responsibilities as a psychiatrist designates. The antidiscrimination provision of the 1980 law would be equally meaningless if it did not prohibit the most significant and burdensome discrimination—the rule that a psychologist could not take responsibility for the diagnosis and treatment of his patients.
In conclusion, it is evident to us that the purpose of the 1978 and 1980 legislation was to change existing regulations and practices that prevented hospitals from fully utilizing the services of clinical psychologists to diagnose and treat patients. In enacting this legislation, the Legislature replaced the specific language originally proposed with more general language—language that was less offensive to the medical profession, less likely to provoke [19]*19difficulties with federal regulations, and above all gave greater scope for hospital discretion than did the original proposals.10 The language it chose, however, is sufficient to make clear its purpose and to accomplish its evident objective.
(d) The Court of Appeal Opinion.
The Court of Appeal also concluded that a psychologist could assume responsibility for diagnosis and treatment of patients, but held he or she could do so in a hospital only “in those instances where a physician has initially ruled out a medical basis for the patient’s mental disorder and determined that it is not subject to medical treatment, and where the patient’s mental disorder does not subsequently become susceptible to medical treatment after admission to the health facility.”
We perceive no statutory basis for this distinction between hospital practice and outpatient practice. Business and Professions Code section 2903 gives a psychologist authority to diagnose and treat patients. It is clear that the licensing law contemplates that he may do so without supervision or prior approval from a physician. The Psychology Licensing Law makes no reference to such supervision or approval, and on an outpatient basis psychologists regularly and routinely diagnose and treat patients independently. No one, including the hospital and physician parties before this court, suggests that psychologists lack authority to do so.
Appellants contend that hospital practice is different because hospitalized patients generally have more serious disorders. It is up to the Legislature, however, to decide whether and how to distinguish between outpatient and hospital practice, and whether any restrictions on the psychologist’s hospital practice should take the form of law, administrative regulation, or hospital rule. The Legislature here has chosen to leave the matter to the discretion of each hospital. By authorizing hospitals to permit psychologists to carry responsibilities consistent with their licensure, it has given hospitals discretion to allow psychologists to assume the same responsibilities vis-avis their hospitalized patients as in an outpatient setting. Under section 1316.5, hospitals may also adopt nondiscriminatory rules that may restrict the psychologist’s scope of practice. Section 1316.5 does not permit the courts, or the Department, to enact such restrictions themselves.
[20]*20Moreover, the first condition laid down by the Court of Appeal opinion— that before a psychologist may take responsibility for a hospitalized patient it must be determined the patient’s disorder has no “medical”11 basis—appears to mistake the distinction between psychology and medicine. That distinction turns on the nature of the treatment each can provide, not the origin of the condition treated. Medical methods, especially medication, are commonly used to treat mental conditions of no known organic origin. Conversely, psychological methods, including testing, counseling, and psychotherapy, are commonly used to treat organic disorders. Psychological tests, for example, are frequently used to diagnose the existence and extent of brain damage resulting from physical injury or disease and, depending on the nature of the damage, psychological methods may be the best or only way to treat the condition.
There is no bright line distinguishing conditions of physical from those of psychological origin. The ultimate cause of a patient’s condition may be uncertain or unknown, and in some cases it may be unnecessary to determine that cause to treat him. Indeed, depending on one’s view of theories concerning the possible genetic or chemical origin of various disorders, it may be impossible for a physician ever to “rule out” the possibility of an organic basis of the patient’s condition. Thus, the authority of the psychologist cannot hinge upon a requirement that the patient’s condition derive from a nonorganic cause.
The Court of Appeal’s second condition—that the disorder is not subject to medical treatment—is also flawed. A patient may receive both medical and psychological treatment. Nothing in the statutes requires that if he receives both, the physician, in the words of appellant’s counsel, must be “the captain of the ship.” If it is necessary to designate one person as the “captain,” nothing in the law denies the hospital discretion to consider such matters as the relative importance of the treatment methods and the prior relationship of the practitioners to the patient.12
IV. Conclusion
A fundamental concern underlies the arguments of appellants, the regulations of the Department, and the opinion of the Court of Appeal. They fear [21]*21that to give responsibility for diagnosis and treatment to a professional who has received less training in the detection of organic illness and in the use of drugs will endanger hospitalized patients. Plaintiffs, of course, dispute the implication that their training and experience leaves them less qualified than psychiatrists to treat hospitalized mental patients.13
Such disputes over the competence of the professions must be decided by the Legislature, not the courts. By defining the licensure of psychologists, the Legislature has necessarily determined that psychologists are generally competent to practice within the scope of that licensure. The Legislature has not itself placed restrictions on that practice in a hospital setting, apart from the requirement in section 1316.5, subdivision (c), that the psychologist must have a doctoral degree and at least two years of clinical experience. Instead, it has chosen to prohibit practices that discriminate against psychologists, while permitting the hospitals to establish nondiscriminatory rules regulating hospital practice of psychologists. We recognize appellants’ concern about the wisdom of the legislative decision, but we cannot sustain regulations that would effectively nullify that decision and continue unchanged practices that the Legislature sought to modify.
We conclude that under California law a hospital that admits clinical psychologists to its staff may permit such psychologists to take primary responsibility for the admission, diagnosis, treatment, and discharge of their patients.14 The 1983 Department regulations requiring a psychiatrist to su[22]*22pervise diagnosis and treatment of all admitted mental patients are therefore invalid. The judgment of the Court of Appeal is reversed, and the case is remanded for further proceedings consistent with this opinion.
Mosk, J., Eagleson, J., and Stone (S. J.), J.,
Presiding Justice, Court of Appeal, Second Appellate District, Division Six, assigned by the Chairperson of the Judicial Council.