dissenting:

I respectfully dissent.

Today’s decision is in conflict with our decision in Williams v. Calderon, 52 F.3d *1229 1465 (9th Cir.1995). 1 In Williams , we affirmed denial of the writ, despite- counsel's failure to examine his client’s past medical records or seek appointment of an independent psychiatrist, and despite five psychiatrists’ declarations submitted with the petition saying that he suffered from diminished capacity when he killed three people after raping one of them. We said that the evidence of Williams’ “intent to kill and his *1230 ability to maturely and meaningfully reflect on his actions was simply overwhelming.” Id. at 1470 . Likewise here.

A. Deficient performance.

Today’s decision does not take seriously the nature of our inquiry. The question is not whether we think Caro’s lawyer could have done something more or better than he did. Nor is it whether, in almost two decades since Caro’s death penalty was imposed, some lawyer or expert can think of something more that could have been said or done to try to persuade the jury not to impose the death penalty. The question is whether counsel’s performance was so deficient that it was as if Caro had no lawyer at all. The answer, plainly, is “no.”

The Supreme Court told us how to analyze petitions for habeas corpus asserting ineffective assistance of counsel in Strickland v. Washington, 466 U.S. 668 , 104 S.Ct. 2052 , 80 L.Ed.2d 674 (1984). The majority does not follow the required analytic approach. Strickland held that the petitioner had not sufficiently made out a case of ineffective assistance or prejudice. In Strickland as here, counsel was accused of failing adequately to develop medical evidence to show mental problems.

Strickland holds that petitioner must show that “counsel made errors so serious that counsel was not functioning as the ‘counsel’ guaranteed the defendant by the Sixth Amendment.” Id. at 687 , 104 S.Ct. 2052 . We are required to apply “highly deferential” judicial scrutiny, which requires that “every effort be made to eliminate the distorting effects of hindsight.” Id. at 689 , 104 S.Ct. 2052 . The majority does not identify errors of that level of seriousness, does not review counsel’s conduct with any deference at all, and applies nothing but hindsight.

The alleged errors of counsel that the majority identifies are (1) failure to investigate Caro’s personal background, (2) failure to consult a neurologist or toxicologist, and (3) failure to provide those everts consulted with sufficient information. The record does not establish that counsel fell below Strickland standards with respect to any of these.

As to the first issue, Caro’s personal background, the majority opinion does not attempt to identify anything that a minimally competent lawyer would have done that Caro’s lawyer did not do. The majority mentions Caro’s personal background and a physician’s claim that his testimony would have been different had the physician known of Caro’s “social and cultural history.” The majority cites Siripongs v. Calderon, 35 F.3d 1308, 1310-13 (9th Cir.1994), for the proposition that “failure to present evidence necessary to bridge a cultural gap may constitute ineffective assistance of counsel.” But the majority does not relate these observations to the question of whether counsel in this case rendered ineffective assistance.

Caro’s lawyer got both of Caro’s parents to testify that they had sorely abused him. He also persuaded Caro’s brother, a brother-in-law, a former girlfriend, an ex-wife, a friend from high school, Caro’s high school football coach, Caro’s boss at work, a vocational instructor from the prison Caro had served time in, a psychologist, and a licensed clinical social worker to testify. They told the jury all about Caro’s background, culture, and suffering. They told the jury about how impoverished the family was, and about how Caro suffered from prejudice on account of his Mexican-Ameriean Yaqui heritage, and how Caro was called “Stinky” in school because he stunk of pesticides. What does the majority think a minimally competent lawyer would have done to investigate and “bridge a cultural gap” that Caro’s lawyer did not do? I have no idea, because the majority opinion does not say. I also have no idea what Caro’s proud heritage has to do with murder.

The meat of the majority opinion is that Caro’s lawyer did not do enough to find the right experts and educate them about Caro’s background. The opinion errs because it lacks a clear focus on the question: whether “counsel made errors so serious that counsel was not functioning as the ‘counsel’ guaranteed the defendant by the Sixth Amendment.” Strickland, 466 U.S. at 687 , 104 S.Ct. 2052 . Suppose an evidentiary hearing were held, at which the most helpful possible propositions for Caro were proved: (1) that the only reason counsel did not do more was that *1231 he did not think of it, and (2) that had counsel done more, he would have found a toxicologist who would testify that pesticide exposure such as Caro had suffered can cause brain damage. That does not add up to a colorable claim of performance below the Strickland standard.

Caro’s lawyer consulted two psychiatrists, a clinical psychologist, and a licensed clinical social worker, in his diligent attempt to develop evidence of some sort of mitigating mental or emotional condition. The psychiatrists were of course medical doctors. One had, in addition to his M.D., two Ph.D. degrees, in physiology and pharmacology. It is the expert’s duty, not the lawyer’s, “to recognize what information he needs in order to render an opinion.” Coleman v. Calderon, 150 F.3d 1105, at 1115 (9th Cir.1998).

The majority accepts Caro’s new lawyers’ claims that his lawyer at sentencing should have consulted a toxicologist or neurologist. Even if that would have been desirable, it does not establish “errors so serious that counsel was not functioning as the ‘counsel’ guaranteed the defendant by the Sixth Amendment.” Strickland, 466 U.S. at 687 , 104 S.Ct. 2052 . A lawyer defending a criminal case is entitled to rely on a physician to tell him whether another physician in a different specialty is needed. People commonly rely on their own physicians to guide them to the appropriate specialists, in matters of their own life and death. It is the doctor’s fault, not the patient’s, if the physician does not offer the appropriate guidance.

Coleman v. Calderon, 150 F.3d 1105, at 1115 (9th Cir.1998) (internal citation and quotation omitted). That one of the psychiatrists now says that if he had learned more about Caro, he would have testified differently, reflects badly on the psychiatrist, not on Caro’s lawyer. If the doctor needed to know more to form a reliable opinion, he should have asked. The two physicians (one also an expert in pharmacology) did not tell Caro’s lawyer to look for evidence of exposure to toxic chemicals or to consult a toxicologist. Evidently they did not think of it, and did not think of asking questions when taking medical histories that would lead them to think of it. So why should a minimally competent lawyer have thought of it?

What Caro’s lawyer’s experts told him gave him no reason to shop for more evidence on brain damage, mental defect, psychiatric problem, or any other such theory to mitigate punishment. The psychologist, Dr. Leifer, found that Caro was “functioning within the superior range of psychometric ability,” with an I.Q. of 124. He found that Caro had “no gross or significantly manifested evidence of psychotic disorganized functioning.” Caro went to college, where he performed satisfactorily until his girlfriend broke up with him in his senior year. Then he joined the Marines, where he did so well that he became a commissioned officer, a lieutenant; he was discharged after the rape and kidnapping. Despite a history that could have led to some sort of relevant brain damage, the two psychiatrists and the psychologist who studied Caro did not find any. If these experts could not think of anything else to ask about Caro’s history, find brain damage, or think to suggest consulting a toxicologist or neurologist, a fortiori Caro’s lawyer was not incompetent for failing to do so.

Caro’s lawyer made the best of what his experts gave him, by having the psychologist testify that despite his intelligence and apparent normality, Caro had a mental defect which could be a result of child abuse. The defect would cause “sudden lapses where the quality of reality testing is gone under aggressive and demonic themes.” Caro’s lawyer built on this with massive evidence of child abuse.

A lawyer who sends his defendant to two psychiatrists and a psychologist to try to find some mitigating evidence regarding mental condition has done enough. That years later, *1232 a new army of lawyers have found a professor at Yale Medical School who has thought of something more that could have been shown, a theory that exposure to pesticides might have damaged Caro’s brain 2 , is entirely irrelevant to the question: whether “counsel made errors so serious that counsel was not functioning as the ‘counsel’ guaranteed the defendant by the Sixth Amendment.” Strickland, 466 U.S. at 687 , 104 S.Ct. 2052 .

B. Prejudice.

The other half of Strickland is that the petitioner must “affirmatively prove prejudice.” Strickland, 466 U.S. at 693 , 104 S.Ct. 2052 . “It is not enough for the defendant to show that the errors had some conceivable effect on the outcome of the proceeding.” Id. Yet a “conceivable effect” is the most that Caro’s new lawyers have even arguably suggested. The Court defined the test as “a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different.” Id. at 694 , 104 S.Ct. 2052 . In Strickland , and in Williams v. Calderon, 52 F.3d 1465 (9th Cir.1995), despite some additional evidence that might have been used to show medical problems, it would have made no difference. Likewise in this case.

The Court instructed us in Strickland that we “must consider the totality of evidence before the judge or jury” in determining whether there was a reasonable probability of a different result, but for unprofessional errors. Yet the majority pointedly avoids considering the “totality” of evidence. A reader of the majority opinion cannot even find out what Caro did. But the jury knew. It is our duty to consider the “totality of evidence,” not just the evidence generating sympathy for Caro, to decide whether introduction of the new toxicology evidence probably would have changed the jury’s collective mind.

At around seven on a summer evening, two teenaged cousins, Mary Booher and Mark Hatcher, went bicycle riding together. Their mother and grandmother went out to meet them a half hour later, and heard a shot. Soon after, they found Mark, shot in the face, dead. Their bicycles were found the next day in a ditch, but Mary had disappeared. She was found five days later in an orange grove, shot in the head, dead and decomposing. Caro had killed the boy, kidnapped the girl, and then killed her too.

After killing the boy and kidnapping the girl, Caro careened away from the scene in his pickup truck, with the bicycles in the bed, and clipped a car in the parking lot of a bar. When he did not stop, the car owner and his friend chased and caught him. Caro got out of his truck and said “don’t hurt me,” while hiding one hand. One of the men told him they were not going to hurt him, but wanted to know if he had insurance. Caro then exposed his hidden hand with a gun in it, shot that man in the face, and shot the other man in the thigh. Then he approached the first man, who was on the ground, and shot him again, in the chest. Then he chased the other man, who was fleeing despite his wound, and continued to shoot at him until he ran out of bullets. Miraculously, both men lived and testified. People v. Caro, 46 Cal.3d 1035 , 251 Cal.Rptr. 757 , 761 P.2d 680 (Cal.1988).

Caro hid his pickup truck. He shaved off his mustache. After getting caught, he repeatedly tried to escape. He gave a false alibi. He did not testify at his trial. Bullet *1233 fragments from Mark’s brain and the wall of a house where the man shot in the thigh had fled, matched Caro’s girlfriend’s gun, which he had access to at the time. The paint on the car clipped in the bar parking lot matched the paint on Caro’s pickup truck. The man shot in the thigh recalled Caro’s license plate number almost exactly. Extensive additional evidence made the case irrefutable. A state superior court jury convicted Caro of two counts of first degree murder with use of a firearm, one count of kidnapping with use of a firearm, and two counts of assault with intent to murder with aggravating factors.

The sentencing jury learned of two additional murders that Caro had apparently committed. Two teenaged girls were found dead in an orchard, shot in the head, with a bullet fragment from Caro’s girlfriend’s gun. The girlfriend could not have done it, because semen was found in the vagina of one of the girls. The jurors had been instructed that they could not consider these murders unless they unanimously found beyond a reasonable doubt that Caro had committed them, and four jurors were not so persuaded, so presumably the jury did not consider them.

A live victim of one of Caro’s former crimes also testified, a superior court commissioner. When she was a law clerk six years before, she took a bus to work, but it stopped and discharged all the passengers some miles away. She tried to hitchhike into work, and Caro picked her up. Once he had her in the car, he pulled a gun and threatened to kill her if she did not do what he said. He kidnapped her, driving her far into the desert. She tried to get away during the four hours he held her by insisting she had to go to the bathroom at a gas station, but Caro came into the ladies’ room and forced her out and forced her back into the car. Far from town, he got her out of the ear, made her strip naked, and raped her. Eventually she made a daring escape into traffic on a freeway. Caro was caught, pleaded guilty to kidnapping in exchange for dismissal of other charges, and served some time.

In Strickland and in Williams , with no more horrible facts, it was held that the additional evidence would probably have made no difference to the outcome. Likewise here, Caro could at most demonstrate a “conceivable effect,” Strickland, 466 U.S. at 693 , 104 S.Ct. 2052 , not a “reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different.” Id. at 694 , 104 S.Ct. 2052 . The jury knew that he had murdered a teenaged boy and girl who had no relationship to him at all. Then he tried to kill two men who got in his way. This was no aberrational lapse from a pattern of good behavior. Six years before, he had kidnapped a woman for an extended period and raped her. Caro’s relentlessness was demonstrated when he pursued his kidnap and rape victim into the ladies’ bathroom, and again when he pursued the two men whose ear he had hit until he ran out of bullets.

In Williams , we said that the evidence “was so clear, lucid and powerful that no psychiatrist would have made a difference.” Williams, 52 F.3d at 1470 . Caro’s lawyer put extensive mitigating expert and lay testimony before the sentencing jury. The jury heard 39 witnesses. In the case at bar, it is even more unpersuasive than in Williams to suggest that one more expert would have made a difference. The defense could have put on a toxicologist to say that Caro’s exposure to pesticides killed some brain cells. The prosecutor could have put on a physician to say that every stroke victim has suffered death of brain cells yet still ordinarily knows right from wrong and does not shoot people. 3 *1234 The jury would have been left with the brutal murder of two young people on bicycles, the relentless attempted murder of'getaway witnesses, the kidnapping and rape six years before, and the demonstrated ability to perform at an extraordinarily high level on intelligence tests and in the Marines.

Because Caro has presented no evidence, either of errors by counsel so grave that it is as though he had no lawyer at all in the Sixth Amendment sense, or of prejudice from the errors he claims counsel made, we should follow our own precedent in Williams and affirm.

. All three of us on the panel missed Babbitt v. Calderon, 151 F.3d 1170 (9th Cir.1998). It came down as we were finishing our responses to each others' draft opinions in this case. The petition for rehearing has educated us about Babbitt . We now have a duty either to follow Babbitt or distinguish it.

I think we cannot distinguish it and must follow it. Our decision in Caro cannot be reconciled with the earlier decision in Babbitt . We are obligated to conform our decision to precedent.

Babbitt and Caro reach opposite conclusions on materially similar facts. The defendants in both capital cases claimed ineffective assistance of counsel. In both cases defense counsel consulted with appropriate medical experts. In both, those experts did not refer defense counsel to other experts (in Babbitt post-traumatic stress disorder experts and in Caro pesticide toxicity brain disorder experts) that habeas counsel argued should have been consulted. In both cases, habeas counsel claimed that defense counsel at trial should have provided his medical experts with additional information that the experts did not ask for. In both, habeas counsel argued that more should have been brought out about the family circumstances of the defendant. Babbitt holds that an evidentiary hearing is not required,. Caro holds that one is. The factual distinctions drawn by the majority are immaterial.

The relevant principle, applicable equally to both cases, is that where the medical experts counsel retained "did not state that they required the services of additional experts,” there "was no need for counsel to seek them out independently.” Babbitt v. Calderon, 151 F.3d 1170, 1174 (9th Cir.1998). And Babbitt rejects habeas counsel’s focus "on what evidence his counsel could have obtained [regarding family and social background] rather than focusing on whether his counsel’s investigative efforts were reasonable.” Id. at 1175 .

Good lawyers do not simply read the experts’ advertisements in the legal newspapers until they find an expert who will say the right thing, and then use him. An expert who is not believed frequently sinks a case. Good lawyers often consult experts they know and trust, and consider their advice before going further. The majority opinion has the unintended, undesirable consequence of creating a Constitutional requirement that defense lawyers engage in inappropriate witness shopping.

The majority evidently misreads my view on prejudice. As explained below, I think there was none, even if Caro’s lawyers’ work had fallen below the Strickland standard, which it did not.

The majority suggests that I should not be permitted to say what a good lawyer would do, but then opines freely about what, in its opinion, any lawyer functioning as 'counsel' guaranteed by the Sixth Amendment (which is to say, a fortiori, any good lawyer) would do. Obviously all of us should and properly do use our experience as lawyers and judges to consider what competent lawyers do and whether "counsel made errors so serious that counsel was not functioning as the 'counsel' guaranteed by the Sixth Amendment.” Strickland v. Washington, 466 U.S. 668, 687 , 104 S.Ct. 2052 , 80 L.Ed.2d 674 (1984).

The evidence about Caro's chemical exposure was massive, and brought out fully to the jury. Caro’s experts had access to it. Dr. Benson employed a clinical social worker who gave him an extensive history of Caro’s childhood and adolescence. Dr. Benson now swears that Caro’s exposure to pesticides is a "necessary predicate” to forming a medical opinion. That may show that Dr. Benson did something wrong years ago, when he formed a medical opinion after taking the history he deemed necessary at that time, and did not explore pesticide exposure. It does not show that the lawyer did anything wrong. Nor does the fact that another of the doctors defense counsel used told Caro that in his opinion, people sentenced to death ought to have the option of committing suicide, show that the lawyer did not function as Sixth Amendment “counsel.”

That Caro experienced skull trauma and chemical exposure that may cause brain damage, does not prove any link between those factors and Caro’s crimes. Aspirin sometimes causes Reyes' syndrome in children, but that does not mean that anyone who has taken aspirin as a child should be assumed to have suffered Reyes' syndrome. If the child did not fall ill with Reyes' syndrome, then it does not matter that he took aspirin. Absence of the consequence makes the potential cause immaterial. One thing may be a medical cause of another in the sense that it increases the probability of the consequence, but the consequence does not happen every time, and if it does not occur in a particular case, then the fact that the predisposing or causal factor was present does not prove anything that matters. Caro’s experts did not find evidence of brain damage. So the fact that chemical exposure and skull trauma such as he had sometimes cause brain damage does not matter.

As it stands, I do not think the district courts and the bar can reconcile the majority decision with Babbitt . The majority has not articulated principles on which a distinction can be made. Without some meaningful principle to distinguish the cases, the decision whether a man lives or dies may ultimately not be controlled by neutral principles of law.

. The majority responds to my dissent by attacking what it calls my "disdain for the Yale Medical School.” I have no idea what my reference to Yale Medical School has to do with "disdain.” The point is that a lawyer does not have a duty to gain access to and testimony from a professor at one of the most eminent institutions in the country, in order to be minimally competent. Though Caro’s lawyer did not scale the walls of Yale, he did consult several other highly qualified experts. They did not refer him to someone more specialized or learned, or advise him that he needed to consult someone else.

Caro's new submissions do not even claim that in December 1981, when the jury returned a verdict of death, the medical literature established that exposure to the chemicals in pesticides may cause brain damage. For all we know from the record, the medical basis for the majority opinion developed in the medical literature during the years that have elapsed since the jury decided this case. If so, no lawyer, however diligent, could have proved then what is claimed now.

. The majority claims that my ignorance of medicine disables me from understanding what the majority, without reference to any authority in the record or learned treatises, claims, that brain damage from stroke "does not cause aggressive behavior." Sometimes it does. "Only a few patients become serious behavior problems or are psychotic after a stroke, but paranoid trends, ill temper, stubbornness, and peevishness are recognized sequelae." Mohr, Fisher and Adams, Cerebrovascular Diseases 1924, in Harrison’s Principles of Internal Medicine (9th ed.1980) (emphasis in original).

Brain damage does not commonly cause murder, so is not necessarily an excuse for murder. Many people suffer destruction of brain cells, from stroke, trauma, toxins, and other causes. Few kill. Even in the unlikely event that a minimally competent lawyer should have found a *1234 witness to testify that Caro’s exposure to pesticides may have damaged his brain, this record still would not establish prejudice from the absence of such testimony. Proving that pesticides may cause brain damage does not prove that they did, and proving that they did does not prove that Caro should be partially excused for murdering the boy and girl riding their bicycles. A jury would not necessarily assume that anyone with brain damage would, as a result, be compelled by his disorder to kill. Considering all the mitigating evidence that did not persuade the jury to refrain from the death penalty, there is no particular reason to suppose that this additional evidence would have mattered.

It is also significant that, even after almost two decades of post-sentencing litigation, Caro's latest lawyers and doctors have not come up with definitive evidence that he is brain damaged now, or was at the time he killed the boy and girl riding their bicycles. His new experts suggest that he may have been brain damaged, based on what some chemicals in pesticides sometimes can do, clinical impressions, and Caro’s own reports of his abnormal feelings and unfortunate history. This is a weak case for prejudice from ineffective assistance. Plenty of people who grew up on farms, constantly exposed to pesticides, feel fine, and do not kill anyone. That some of the individuals exposed to certain chemicals may suffer brain damage, which may contribute to disorders of feeling and thought, does not establish that all persons so exposed are free of responsibility for what they do.