concurring:

I am pleased to join Chief Judge Schroeder’s opinion. I write only to explain that for me the fulcrum of this dispute is not the First Amendment right of the doctors. That right certainly exists and its impairment justifies the district court’s injunction for the reasons well explained by Chief Judge Schroeder. But the doctors’ interest in giving advice about the medical use of marijuana is somewhat remote and impersonal; they will derive no direct benefit from giving this advice, other than the satisfaction of doing their jobs well. At the same time, the burden of the federal policy the district court enjoined falls directly and personally on the doctors: By speaking candidly to their patients about the potential benefits of medical marijuana, they risk losing their license to write prescriptions, which would prevent them from functioning as doctors. In other *640 words, they may destroy their careers and lose their livelihoods. 1

This disparity between benefits and burdens matters because it makes doctors peculiarly vulnerable to intimidation; with little to gain and much to lose, only the most foolish or committed of doctors will defy the federal government’s policy and continue to give patients candid advice about the medical uses of marijuana. 2 Those immediately and directly affected by the federal government’s policy are the patients, who will be denied information crucial to their well-being, and the State of California, whose policy of exempting certain patients from the sweep of its drug laws will be thwarted. In my view, it is the vindication of these latter interests— those of the patients and of the state— that primarily justifies the district court’s highly unusual exercise of discretion in enjoining the federal defendants from even investigating possible violations of the federal criminal laws.

In 1996, the people of California, acting by direct initiative, adopted a narrow exemption from their laws prohibiting the cultivation, sale and use of marijuana. The exemption applies only to patients whose physicians recommend or prescribe the drug for medical purposes. To those unfamiliar with the issue, it may seem faddish or foolish for a doctor to recommend a drug that the federal government finds has “no currently accepted medical use in treatment in the United States,” 21 U.S.C. § 812 (b)(1)(B). But the record in this case, as well as the public record, reflect a legitimate and growing division of informed opinion on this issue. A surprising number of health care professionals and organizations have concluded that the use of marijuana may be appropriate for a *641 small class of patients who do not respond well to, or do not tolerate, available prescription drugs. 3

Following passage of the California initiative, the White House Office of National Drug Control Policy commissioned the National Institute of Medicine of the National Academy of Sciences (IOM) to review the scientific evidence of the therapeutic application of cannabis. See Inst. of Med., Marijuana and Medicine: Assessing the Science Base (Janet E. Joy et al. eds., 1999) [hereinafter IOM Report], available at http://www.nap.edu/books/0309071550/ html. The year-long study included scientific workshops, analysis of relevant scientific literature and extensive consultation with biomedical and social scientists. Id. at 15 . It resulted in a 250-plus-page report which concluded that “[s]cientific data indicate the potential therapeutic value of cannabinoid drugs, primarily THC, for pain relief, control of nausea and vomiting, and appetite stimulation,” id. at 179 .

The IOM Report found that marijuana can provide superior relief to patients who suffer these symptoms as a result of certain illnesses and disabilities, in particular metastic cancer, HIV/AIDS, multiple sclerosis (MS), spinal cord injuries and epilepsy, and those who suffer the same symptoms as side effects from the aggressive treatments for such conditions. See id. at 53, 142, 153-54, 157, 160 . As a consequence, the IOM Report cautiously endorsed the medical use of marijuana. See id. at 179 . 4

At about the time the IOM study got underway, the British House of Lords — a body not known for its wild and crazy views — opened public hearings on the medical benefits and drawbacks of cannabis. Like the IOM, the Lords concluded that “cannabis almost certainly does have genuine medical applications, especially in treating the painful muscular spasms and other symptoms of MS and in the control of other forms of pain.” Select Comm, on Sci. & Tech., House of Lords, Sess. 1997- *642 98, Ninth Report, Cannabis: The Scientific and Medical Evidence: Report § 8.2 (Nov. 4, 1998), available at http://www. publications.parliament.uk/pa/1d199798/1d-select/ldsctech/151/15101.htm. The Lords recommended that the British government act immediately “to allow doctors to prescribe an appropriate preparation of cannabis, albeit as an unlicensed medicine.” Id. § 8.6.

In June 2001, Canada promulgated its Marihuana Medical Access Regulations after an extensive study of the available evidence. See Marihuana Medical Access Regulations, SOR 2001-227 (June 14, 2001), available at http://laws.justice.gc. ca/en/C-38.8/SOR-2001-227/index.html. The new regulations allow certain persons to cultivate and possess marijuana for medical use, and authorize doctors to recommend and prescribe marijuana to patients who are suffering from severe pain, muscle spasms, anorexia, weight loss or nausea, and who have not found relief from conventional therapies. See Office of Cannabis Med. Access, Health Canada, Medical Access to Marijuana —How the Regulations Work, at http://www.hc-sc.gc.ca/hecs-sesc/ocma/bckdr_l-0601.htm (last visited Aug. 23, 2002). 5

Numerous other studies and surveys support the use of medical marijuana in certain limited circumstances. 6 The federal government itself has conducted studies on the subject, and continues to fund and provide the marijuana for studies conducted by private researchers. See, e.g., Bill Workman, Pot Study in Spotlight: San Mateo County’s Clinical Trial Is a First in U.S., S.F. Chron., July 25, 2001, at A13; see also University of California Center for Medicinal Cannabis Research, Research, at http://www.cmcr.ucsd.edu/geninfo/re-search.htm (last visited Aug. 23, 2002) (list *643 ing eleven studies, nine of which have received regulatory approval, that will use federally supplied marijuana). Finally, the medical histories of individuals who have received and continue to receive medical marijuana from the federal government (reproduced in the Appendix) provide compelling support for the view that medical marijuana can make the difference between a relatively normal life and a life marred by suffering.

No doubt based on this and similar evidence, seven states (Alaska, Arizona, Colorado, Maine, Nevada, Oregon and Washington) have followed California in enacting medical marijuana laws by voter initiative, see Alaska Stat. Ann. §§ 11.71.090 , 17.37.010-.080; Ariz.Rev. Stat. § 13-3412.01; Colo. Const. art. XVIII, § 14; Me.Rev.Stat. Ann. tit. 22, § 2383-B5; Nev. Const. art. 4, § 38; Or. Rev.Stat. §§ 475.300-.346; Wash. Rev. Code §§ 69 .51A.005-.902; one other state (Hawaii) has done so by legislative enactment, see Haw.Rev.Stat. §§ 329-121 to - 128. The total number of states that have approved marijuana for medical purposes now stands at nine.

The evidence supporting the medical use of marijuana does not prove that it is, in fact, beneficial. There is also much evidence to the contrary, and the federal defendants may well be right that marijuana provides no additional benefit over approved prescription drugs, while carrying a wide variety of serious risks. 7 What matters, however, is that there is a genuine difference of expert opinion on the subject, with significant scientific and anecdotal evidence supporting both points of view. See (Medical) MarijuanaInfo.org, at http://www.marijuanainfo.org (last visited Aug. 27, 2002) (exhaustive catalog of information and expert opinion on both sides of the medical marijuana debate). For the great majority of us who do not suffer from debilitating pain, or who have not watched a loved one waste away as a result of AIDS-induced anorexia, see IOM Report at 154, it doesn’t much matter who has the better of this debate. But for patients suffering from MS, cancer, AIDS or one of the other afflictions listed in the IOM report, and their loved ones, obtaining candid and reliable information about a possible avenue of relief is of vital importance.

It is well established that the right to hear — the right to receive information — is no less protected by the First Amendment than the right to speak. See, e.g., Bd. of Educ. v. Pico, 457 U.S. 853, 866-67 , 102 S.Ct. 2799 , 73 L.Ed.2d 435 (1982); Va. State Bd. of Pharmacy v. Va. Citizens Consumer Council, Inc., 425 U.S. 748, 756-57 , 96 S.Ct. 1817 , 48 L.Ed.2d 346 (1976); Kleindienst v. Mandel, 408 U.S. 753, 762-63 , 92 S.Ct. 2576 , 33 L.Ed.2d 683 (1972). Indeed, the right to hear and the right to speak are flip sides of the same coin. As Justice Brennan put it pithily, “It would be a barren marketplace of ideas that had only sellers and no buyers.” Lamont v. Postmaster General, 381 U.S. 301, 308 , 85 S.Ct. 1493 , 14 L.Ed.2d 398 (1965) (Brennan, J., concurring), quoted with approval in Pico, 457 U.S. at 867 , 102 S.Ct. 2799 . This does not mean, however, that the right to speak and the right to listen always carry the same weight when a court exercises its equitable discretion. In this case, for instance, it is perfectly clear that the harm to patients from being denied the right to receive candid medical advice is far greater than the harm to doctors from being unable to deliver such advice. 8 While denial of the right to speak *644 is never trivial, the simple fact is that if the injunction were denied, the doctors would be able to continue practicing medicine and go on with their lives more or less as before. It is far different for patients who suffer from horrible disabilities, such as plaintiff Judith Cushner, a mother of two and the director of a preschool program, who has fought breast cancer since 1989, and who only found relief from the debilitating effects of chemotherapy by smoking cannabis to counteract nausea, retching and chronic mouth sores; plaintiff Keith Vines, an Assistant District Attorney, decorated Air Force officer and father, whose bout with AIDS had caused him to lose more than 40 pounds of lean body mass, which he was only able to recover by using cannabis to stimulate his appetite; and many others like them. Enforcement of the federal policy will cut such patients off from competent medical advice and leave them to decide on their own whether to use marijuana to alleviate excruciating pain, nausea, anorexia or similar symptoms. But word-of-mouth and the Internet are poor substitutes for a medical doctor; information obtained from chat rooms and tabloids cannot make up for the loss of individualized advice from a physician with many years of training and experience.

A few patients may be deterred by the lack of a doctor’s recommendation from using marijuana for medical purposes, but I suspect it would be very few indeed, because the penalties under state law for possession of small amounts of the drug are trivial. See Cal. Health & Safety Code § 11357 (b) (making small-quantity possession a misdemeanor carrying a maximum $100 fine). A far more likely consequence is that, in the absence of sound medical advice, many patients desperate for relief from debilitating pain or nausea would self-medicate, and wind up administering the wrong dose or frequency, or use the drug where a physician would advise against it. Whatever else the parties may disagree about, they agree that marijuana is a powerful and complex drug, the kind of drug patients should not use without careful professional supervision. 9 The *645 unintended consequence of the federal government’s policy — a policy no doubt adopted for laudable reasons — will be to dry up the only reliable source of advice and supervision critically ill patients have, and drive them to use this powerful and dangerous drug on their own.

Which points to the second important interest impaired by the federal government’s policy: California’s interest in legalizing the use of marijuana in certain limited circumstances, so that critically ill patients may use it if and only if it is medically advisable for them to do so. The state relies on the recommendation of a state-licensed physician to define the line between legal and illegal marijuana use. The federal government’s policy deliberately undermines the state by incapacitating the mechanism the state has chosen for separating what is legal from what is illegal under state law. Normally, of course, this would not be a problem, because where state and federal law collide, federal law prevails. See Gade v. Nat’l Solid Wastes Mgmt. Ass’n, 505 U.S. 88, 108, 112 S.Ct. 2374 , 120 L.Ed.2d 73 (1992); cf. United States v. Oakland Cannabis Buyers’ Coop., 532 U.S. 483 , 121 S.Ct. 1711 , 149 L.Ed.2d 722 (2001). In the circumstances of this case, however, I believe the federal government’s policy runs afoul of the “commandeering” doctrine announced by the Supreme Court in New York v. United States, 505 U.S. 144, 112 S.Ct. 2408 , 120 L.Ed.2d 120 (1992), and Printz v. United States, 521 U.S. 898, 117 S.Ct. 2365 , 138 L.Ed.2d 914 (1997).

New York and Printz stand for the proposition that “[t]he Federal Government may neither issue directives requiring the States to address particular problems, nor command the States’ officers, or those of their political subdivisions, to administer or enforce a federal regulatory program.” Printz, 521 U.S. at 935 , 117 S.Ct. 2365 . Applied to our situation, this means that, much as the federal government may prefer that California keep medical marijuana illegal, 10 it cannot force the state to do so. Yet, the effect of the *646 federal government’s policy is precisely that: By precluding doctors, on pain of losing their DEA registration, from making a recommendation that would legalize the patients’ conduct under state law, the federal policy makes it impossible for the state to exempt the use of medical marijuana from the operation of its drug laws. In effect, the federal government is forcing the state to keep medical marijuana illegal. But preventing the state from repealing an existing law is no different from forcing it to pass a new one; in either case, the state is being forced to regulate conduct that it prefers to leave unregulated.

It is true that by removing state penalties for the use of marijuana, a doctor’s recommendation may embolden patients to buy the drug, and others to sell it to them, in violation of federal law. But the doctors only help patients obtain the drug by removing state penalties for possession and sale; they do not purport to exempt patients or anyone else from federal law, nor could they. If the federal government could make it illegal under federal law to remove a state-law penalty, it could then accomplish exactly what the commandeering doctrine prohibits: The federal government could force the state to criminalize behavior it has chosen to make legal. 11 That patients may be more likely to violate federal law if the additional deterrent of state liability is removed may worry the federal government, but the proper response — -according to New York and Printz — is to ratchet up the federal regulatory regime, not to commandeer that of the state.

Nor does the state have another mechanism available to distinguish lawful from unlawful conduct. The state law in question does not legalize use of marijuana by anyone who believes he has a medical need for it. Rather, state law is closely calibrated to exempt from regulation only patients who have consulted a physician. And the physician may only recommend marijuana when he has made an individualized and bona fide determination that the patient is within the small group that may benefit from its use. If medical doctors are unable or unwilling to make this determination because they fear losing their DEA registration, there is no one who can take their place. Nurses and paramedics aren’t qualified to do it, which is why they don’t have authority to write prescriptions in the first place. Lawyers, judges and police can’t do it, except by asking the advice of physicians. State administrators can’t do it. If doctors are taken out of the picture- — -as the federal policy clearly aims to do — the state’s effort to withdraw its criminal sanctions from marijuana use by the small group of patients who could benefit from such use is bound to be frustrated. The federal government’s attempt to target doctors — eliminating the only viable mechanism for distinguishing between-legal and illegal drug use — is a backdoor attempt to “control or influence the manner in which States regulate private parties.” Reno v. Condon, 528 U.S. 141, 150 , 120 S.Ct. 666 , 145 L.Ed.2d 587 (2000) (internal quotation marks omitted).

This is not a situation like United States v. Moore, 423 U.S. 122 , 96 S.Ct. 335 , 46 L.Ed.2d 333 (1975), where a doctor used *647 his prescriptions license to circumvent the federal drug laws. Moore conducted inadequate or no medical examinations, ignored the results of the few tests he did perform, prescribed however many tablets the “patient” asked for and graduated his fee according to the number he prescribed. See id. at 142-43 , 120 S.Ct. 666 . The Court concluded that Moore had abandoned his professional role and effectively become a drug dealer. Here, by contrast, doctors are performing their normal function as doctors and, in so doing, are determining who is exempt from punishment under state law. If a doctor abuses this privilege by recommending marijuana without examining the patient, without conducting tests, without considering the patient’s medical history or without otherwise following standard medical procedures, he will run afoul of state as well as federal law. But doctors who recommend medical marijuana to patients after complying with accepted medical procedures are not acting as drug dealers; they are acting in their professional role in conformity with the standards of the state where they are licensed to practice medicine. The doctor-patient relationship is an area that falls squarely within the states’ traditional police powers. The federal government may not force the states to regulate that relationship to advance federal policy.

The commandeering problem becomes even more acute where Congress legislates at the periphery of its powers. The Constitution authorizes Congress to regulate activities that affect interstate commerce. But that authority is not boundless. As the Supreme Court recently reminded us, Congress must exercise its power so as to preserve “the Constitution’s distinction between national and local authority.” United States v. Morrison, 529 U.S. 598, 615 , 120 S.Ct. 1740 , 146 L.Ed.2d 658 (2000). That distinction, in turn, was designed “so that the people’s rights would be secured by the division of power.” Id. at 616 n. 7, 120 S.Ct. 1740 ; see also U.S. Term Limits, Inc. v. Thornton, 514 U.S. 779, 838 , 115 S.Ct. 1842 , 131 L.Ed.2d 881 (1995) (Kennedy, J., concurring) (“The Framers split the atom of sovereignty. It was the genius of their idea that our citizens would have two political capacities, one state and one federal, each protected from incursion by the other.”). The Supreme Court’s recent Commerce Clause jurisprudence is cut from the same cloth as the commandeering principle; both protect the duality of our unique system of government. The Commerce Clause limits the scope of national power, while the commandeering doctrine limits how Congress may use the power it has. These checks work in tandem to ensure that the federal government legislates in areas of truly national concern, while the states retain independent power to regulate areas better suited to local governance.

Medical marijuana, when grown locally for personal consumption, does not have any direct or obvious effect on interstate commerce. Cf. Oakland Cannabis Buyers’ Coop., 532 U.S. at 495 n. 7, 121 S.Ct. 1711 (reserving “whether the Controlled Substances Act exceeds Congress’ power under the Commerce Clause”). Federal efforts to regulate' it considerably blur the distinction between what is national and what is local. But allowing the federal government, already nearing the outer limits of its power, to act through unwilling state officials would “obliterate the distinction” entirely. United States v. Lopez, 514 U.S. 549, 557 , 115 S.Ct. 1624 , 131 L.Ed.2d 626 (1995) (internal quotation marks omitted). 12

*648 It may well be, as our opinion holds, that interference with the rights of doctors to speak is sufficient to support the district court’s injunction. Nevertheless, it remains a significant step for a court to enjoin the prosecution and even investigation of what federal officials believe may be a violation of federal law. See, e.g., Bresgal v. Brock, 843 F.2d 1163, 1171 (9th Cir.1987); Jett v. Castaneda, 578 F.2d 842, 845 (9th Cir.1978). In affirming the district court, I therefore find comfort in knowing that the interests of the patients, and those of the state, provide significant additional support for the district court’s exercise of discretion.

Appendix

From 1978 to 1992, the federal government conducted its own medical marijuana program. Today, the government continues to supply individuals who participated in this program with marijuana under its Compassionate Care program; they are among the few people in the country who can use the drug legally. Together with the American Public Health Association and other health care and medical organizations, individuals in this group filed an amicus brief supporting the plaintiffs. The following are their personal statements, taken from that brief.

Barbara M. Douglass was diagnosed with Multiple Sclerosis in 1988 at the age of 22. In 1991, Ms. Douglass began receiving herbal cannabis from the United States government upon the advice and assistance of her physician. Prior to this date, Ms. Douglass had never tried cannabis. Each month, the government provides her physician with one can containing three hundred cannabis cigarettes, each weighing 7/10 oz. Ms. Douglass and her physician report that herbal cannabis provides relief from pain and spasms and stimulates her appetite to counteract the effects of wasting syndrome from which she suffered prior to using cannabis. Ms. Douglass has never experienced any adverse side effects from marijuana. Without cannabis, Ms. Douglass believes she would not be alive today.

George Lee McMahon was born July 22, 1950, with Nail Patella Syndrome, a rare genetic disorder that causes severe pain, nausea and muscle spasms. Mr. McMahon tried conventional medications to treat his symptoms, but found the side effects of these medications to be intolerable. In the early 1980s, Mr. McMahon discovered that herbal cannabis alleviated his pain, nausea and spasms, stimulated his appetite and allowed him to sleep through the night. In 1988, Mr. McMahon informed his physician that he was successfully self-medicating with cannabis. His physician ordered him to cease his cannabis use and return to prescription medications. Over the following six months, Mr. McMahon’s health progressively degenerated. Mr. McMahon’s physician then helped Mr. McMahon apply to the federal government’s Compassionate Care IND Program. In March 1990, Mr. McMahon was accepted into the program and for the past decade has received 300 cannabis cigarettes each month from the United States government. Mr. McMahon and his physician believe that without cannabis Mr. McMahon would not be alive today.

Elvy Musikka was diagnosed with glaucoma in 1975 at the age of 36. She tried conventional medications to treat her con *649 dition, but could not tolerate them. Reluctantly, in 1976, she decided to try herbal cannabis at the advice of her physician. The cannabis provided her immediate relief, substantially lowering her intraocular pressure as no other medication had, with few side effects. Ms. Musikka ingests cannabis by smoking it, as well as eating it in baked goods and olive oil. Fearful of the legal consequences of smoking cannabis, Ms. Musikka underwent several risky surgeries in an attempt to correct her condition, but they were unsuccessful and left her blind in one eye. In 1988, Ms. Musik-ka was arrested in Florida and charged with cannabis possession. She challenged her conviction in the Florida Supreme Court, where she prevailed, becoming the first person in that state to establish a medical necessity defense for cannabis. Shortly thereafter, the federal government enrolled Ms. Musikka in its medical cannabis program and has provided her with one and one-half pounds of herbal cannabis on a quarterly basis ever since. Ms. Musikka and her physician believe that if she were deprived of cannabis she would go blind.

Irvin Henry Rosenfeld was diagnosed at age 10 with multiple congenital cartilaginous exostosis, a disease causing the continuous growth of bone tumors, and the generation of new tumors, on ends of most of the long bones in his body. He was told he would not survive into adulthood. In an attempt to treat the painful symptoms of this disease, he was prescribed high doses of opioid analgesics, muscle relaxants and anti-inflammatory medications, which he took on a daily basis, but which had minimal efficacy and produced debilitating side effects. In 1971, Mr. Rosenfeld began using smoked herbal cannabis with the approval and under the supervision of a team of physicians. Mr. Rosenfeld found the cannabis highly efficacious in alleviating pain, reducing swelling, relaxing muscles and veins that surround the bone tumors, and preventing hemorrhaging. In 1982, the United States government, operating under the Compassionate Care IND Program, at the request of his physicians, began supplying Mr.' Rosenfeld with herbal cannabis to treat his condition. For the past 19 years, the government has consistently provided him with a 75-day supply of herbal cannabis, totaling 33 ounces per shipment. Mr. Rosenfeld smokes 12 marijuana cigarettes a day to control the symptoms of his disease. In the 30 years that Mr. Rosenfeld has used herbal cannabis as a medicine, he has experienced no adverse side effects (including no “high”), has been able to discontinue his prescription medications, and has worked successfully for the past 13 years as a stockbroker handling multi-million dollar accounts. Mr. Rosenfeld and his physicians believe that but for herbal cannabis, Mr. Rosenfeld might not be alive, or, at the very least, would be bed-ridden.

. Dr. Neil M. Flynn, Professor at the University of California at Davis School of Medicine, offers one perspective:

. As Alice Pasetta Mead explained in her expert report:

The federal government’s policy had precisely this effect before it was enjoined by the district court. Dr. Milton N. Estes, Associate Clinical Professor in the Department of Obstetrics, Gynecology and Reproductive Medicine at the University of California-San Francisco (UCSF), reports:

And Dr. Stephen O'Brien, former co-director of UCSF HIV Managed Care, similarly notes:

. I am indebted to the brief of amici American Public Health Association et al. for its lucid and forceful analysis of this issue. Much of the discussion in the text is plagiarized from that brief. For ease of readability, I dispense with further attribution.

. The IOM Report concluded:

Id. at 179.

. In 1988, an Administrative Law Judge of the Drug Enforcement Administration similarly concluded that certain patients should have access to medical marijuana. See In re Marijuana Rescheduling Petition, No. 86-22 (Drug Enforcement Admin. Sept. 6, 1988). ALJ Young found:

Id. at 68. The DEA Administrator did not endorse the ALJ’s findings. See 54 Fed.Reg. 53,767 (Dec. 29, 1989).

. See, e.g., Clive Cookson, High Hopes for Cannabis To Relieve Pain, Fin. Times, Sept. 4, 2001, National News, at 4 (“Cannabis extract is proving remarkably effective at relieving severe pain in patients with multiple sclerosis and spinal injury....”); David Baker et al., Cannabinoids Control Spasticity and Tremor in a Multiple Sclerosis Model, 404 Nature 84 (2000) (finding therapeutic potential in the use of cannabis to control the debilitating symptoms of MS); William J. Martin, Basic Mechanisms of Cannabinoid-Induced Analgesia, Int'l Ass’n for the Study of Pain Newsletter, Summer 1999, available at http: //www.halcyon.com/iasp/TC99Summer.html (noting that cannabinoids can reduce pain); Richard E. Doblin & Mark A.R. Kleiman, Marijuana as Antiemetic Medicine: A Survey of Oncologists’ Experiences and Attitudes, 9 J. Clinical Oncology 1314 (1991) (reporting that a majority of oncologists surveyed thought marijuana should be available by prescription); H.M. Meinck et al., Effect of Cannabinoids on Spasticity and Ataxia in Multiple Sclerosis, 236 J. Neurology 120 (1989) (concluding from a neurological study that herbal cannabis provided relief from both muscle spasms and ataxia, a combined benefit not found in other available medications); Vincent Vinciguerra et al., Inhalation Marijuana as an Antiemetic for Cancer Chemotherapy, 88 N.Y. St. J. Med. 525 (1988) (finding that 78% of patients who were unresponsive to standard antiemetics responded positively to cannabis).

. See 66 Fed.Reg. 20,038 (Apr. 18, 2001) (citing sources).

. Dr. Stephen Eliot Follansbee, Chief of Staff at Davies Medical Center, noted the importance of this information to patients:

. Patients who use marijuana for medical purposes must strike a delicate balance; they must take enough of the drug so that they get needed relief from pain or other symptoms, but not so much as to induce the drug’s well-known hallucinogenic side-effects, which interfere with daily life activities. Valerie A. Corral, who suffered from severe seizures before using medical marijuana, explains that she only needs "a few puffs of marijuana” to find relief that over fifteen pills a day could not provide. Judith Cushner recalls that smoking small amounts of marijuana as part of her cancer treatment was neither “a regular part of [her] day, nor did it become a habit.” She states: "I smoked it only when nausea or retching commenced or worsened, usually in conjunction with a treatment session. There were weeks when I smoked it every few days. There were also periods when I didn’t smoke for weeks at a time. Each time I felt a wave of nausea coming on, I inhaled just two or three puffs and it subsided.” Similarly, Assistant District Attorney Keith Vines, countering AIDS-induced wasting syndrome, found that "it took only two or three puffs from a marijuana cigarette for my *645 appetite to return.... Because I only required a small dose to stimulate my appetite, I did not need to get stoned in order to eat.” Patients lacking the benefit of medical guidance may well take more than appropriate to alleviate their symptoms, unnecessarily suffering the drug's powerful side-effects.

. Following the passage of California's medical marijuana initiative, federal officials expressed concern that the measure would seriously affect the federal government's drug enforcement effort. They explained that federal drug policies rely heavily on the states' enforcement of their own drug laws to achieve federal objectives. In hearings before the Senate Judiciary Committee, DEA Administrator Thomas A. Constantine stated:

Prescription for Addiction? The Arizona and California Medical Drug Use Initiatives: Hearing Before the S. Comm, on the Judiciary, 104th Cong. 42-43, 45 (1996) [hereinafter Judiciary Hearing] (statement of Thomas A. Constantine); see also Tim Golden, Doctors Are Focus of Plan To Fight New Drug Laws: Officials Deal with Narcotics Medical Use, N.Y. Times, Dec. 23, 1996, at A10 (“Federal agents and prosecutors in fact pursue only a small fraction of the country's drug cases. In most districts, officials said, United Slates Attorneys bring Federal charges only if a marijuana case involves the cultivation of at least 500 plants grown indoors, 1,000 plants grown outdoors, or the possession of more than 1,000 pounds.”).

. Federal defendants concede that this is their goal, arguing that the doctors’ actions are illegal because "[w]ithout [the doctors’] clinical recommendation or approval, patients and their primary caregivers are unable to invoke [Proposition 215's] protections from criminal prosecution or sanction under state law." Appellants’ Reply Br. at 6 (internal quotation marks omitted) (emphasis added). General Barry McCaffrey, Director of the Office of National Drug Control Policy, made the same point: "Federal law is not at stake; the actions of local law enforcement are.” Judiciary Hearing, supra, at 40.

. The reluctance of state officials to enforce federal drag policies against medical marijua *648 na patients is not merely theoretical. See William Booth, Santa Cruz Defies U.S. on Marijuana: City Officials Vow To Defend Medical Uses, Wash. Post, Sept. 18, 2002, at A3. It is precisely such conflicts between state and federal officials that the commandeering doctrine is designed in part to prevent.