dissenting:
Rozelle and Armstrong, two black criminal defendants, present one of the most serious claims any person can raise — that the government has engaged in racial discrimination in selecting which offenders to prosecute. Such a claim deserves the most careful examination, for the ability to decide whether to bring charges gives prosecutors an awesome power to affect people’s lives. When prosecutors use this power in a racially discriminatory manner, courts must step in to protect the objects of that conduct. Moreover, when one of our experienced district judges finds credible evidence that federal prosecutors are engaging in such impermissible discrimination, we should be most hesitant to prevent her from gathering further information that will permit a full examination of the claim. Yet the majority here abruptly cuts off exploration of the explosive charge made by these *1439two defendants, concluding, surprisingly, that Judge Marshall abused her discretion in ordering further discovery. I disagree strongly with my colleagues’ decision. The defendants have shown far more than a “colorable basis” for a belief that the practice of racially discriminatory prosecution exists. Moreover, the district judge’s own observations and experience with the United States Attorney’s office provide substantial additional support for the discovery order. For these reasons, and because recent studies indicate that further discovery might conclusively prove that prosecutors have engaged in unconstitutional conduct, I dissent.
I.
At the outset, it is important to make plain the narrow scope of our review, a scope which the majority clearly exceeds. First, we are reviewing only the district court’s discovery order. The district court has not decided that the defendants have shown unconstitutional selective prosecution, and the defendants do not have to prove impermissible discrimination to obtain discovery. If they could make such a showing without any discovery, there would be no need for discovery in the first place. Because we review only the district court’s decision to allow the defendants to gather more evidence, it is not our job to decide whether the defendants have made an ultimate showing of unconstitutional discrimination. Their burden in cases of this nature is far less.
Second, we review the district court’s decision to order discovery for abuse of discretion. United States v. Bourgeois, 964 F.2d 935, 937 (9th Cir.1992). “The task of safeguarding the rights of criminal defendants ultimately rests with the experienced men and women who preside in our district courts.” United States v. Balough, 820 F.2d 1485, 1491 (9th Cir.1987). District judges are uniquely situated to observe possible discrimination in the government’s charging decisions. They have much more experience with the policies and practices of the United States Attorney in their district than do we, and they are obviously in a better position to observe a pattern of discrimination than are individual defendants. See United States v. Redondo-Lemos, 955 F.2d 1296, 1298, 1302 (9th Cir.1992). Accordingly, when a district court, knowledgeable of the practices and performance of a particular United States Attorney’s office, finds a defendant’s showing of selective prosecution sufficiently persuasive to warrant further inquiry, we should only overturn its decision based on a very clear showing of error. Were my colleagues to afford the district court’s determination the deference to which it is entitled, they would have no choice but to affirm.
II.
A.
The effect of the majority’s decision is to create three highly artificial categories of cases. At one extreme are the cases in which a district judge completely ignores his or her own experience and observations and makes clear on the record that the discovery order is based solely on the submissions of the parties. Under the majority’s opinion, this category of cases is governed by the Bourgeois standard, and the evidence submitted by the parties must create a “color-able basis” for the discovery order.1 At the other extreme are those cases in which, as in Redondo-Lemos, a district judge develops a suspicion of discriminatory conduct based purely on his own day-to-day observations *1440and orders discovery or a hearing without any prompting by the parties. In this category of cases, the “suspicion” rule set forth in Redondo-Lemos requires a reviewing court to defer to the district judge's determinations.
In between these extremes lie the cases which surely arise most frequently — those in which a district judge’s decision to order discovery is based in part on the evidence submitted by the parties and in part on his own personal experience, • observations, and suspicions. Although in its opinion the majority, remarkably, does not acknowledge the existence of this category and thus does not discuss the standard to be applied in mixed-basis cases, it is clear that, whether these eases are viewed through the framework provided by Redondo-Lemos or that provided by Bourgeois, an appellate court should overturn a district court’s order permitting discovery in such eases in only the rarest of circumstances. When the evidence presented by a defendant, combined with a district judge’s own observations, convinces the judge that further inquiry is warranted, it should ordinarily be enough to satisfy any of the standards we have enunciated.
B.
The majority’s decision to reverse the district judge is based on its conclusion that this case falls into the first of the three categories — that the record makes clear that Judge Marshall deliberately put aside her day-today observations and experience with the United States Attorney’s office and based her decision solely on the parties’ submissions. My colleagues conclude that in this case the district judge relied in no part on her own observations: “The record demonstrates that the district court based its decision on the evidence presented by the defendants, not on its own day to day observations.” Ante at 1435-36. My colleagues appear to concede that when “the district court develops a suspicion of unconstitutional conduct on the basis of its own day-to-day observations, this will be deemed a sufficient pri-ma facie showing” to support a further inquiry by the district court, including limited discovery. Redondo-Lemos, 955 F.2d at 1302. However, instead of treating this as a mixed-basis case, in which a district court’s review of the evidence, augmented by its experience with the particular prosecutor’s office, is entitled to substantial deference, the majority looks only at the evidence presented by the defendants. My colleagues then hold that the defendants’ submissions fail to meet the Bourgeois standards for discovery.
C.
I have three objections to the majority’s decision. First, as I have suggested, I believe that its creation of three arbitrary categories unnecessarily and improperly complicates this area of the law. Discovery orders in discriminatory prosecution eases should be judged by a single standard, one that draws on the principles enunciated in both Redon-do-Lemos and Bourgeois. This standard should be appropriate for use in the vast majority of eases — those in which the district judge makes a decision to order discovery based in part on the evidence submitted by the parties and in part on his own observations and experience. It should apply uniformly, regardless of whether the district court relies only slightly on the evidence presented by the parties and most substantially on his own experience, or vice versa, or even if the district court disclaims any knowledge of the general subject. In any event, the standard should require reversal of an order permitting discovery only when, giving substantial weight to the district court’s own observations, the court could not rationally have reached the judgment it did.
Even assuming the majority’s three-tiered approach is coherent or sensible, I disagree strongly with its decision to place this case in the first category — to classify it as a case in which the district court ignored its own experience and relied solely on the evidence presented by the parties. A fair view of the record demonstrates to me that Judge Marshall’s decision to order discovery was based at least in part on her own observations of and experience with the United States Attorney’s office.2 If my colleagues were to con*1441sider that factor in combination with the evidentiary showing they reject, they would surely be required to uphold the district court’s order. Thus, on remand Judge Marshall will be free to issue a new discovery order if she bases that new order in part upon her own day-to-day experience.
Finally, I believe that the defendants have made a sufficient evidentiary showing, wholly apart from the district judge’s observations, to support the discovery order previously issued. Thus, even if I agreed with the majority that the district court entirely ignored its day-to-day observations and focused solely on the parties’ evidentiary submissions, I would still affirm under the Bourgeois standard. I explain why below.
III.
The Bourgeois standard is not as difficult to meet as the majority’s conclusion in this case might lead one to believe. Because we thought that a “nonfrivolousness” standard would allow a defendant too easily to delay a prosecution and initiate intrusive discovery, and that a “prima facie ease” standard would often mate it impossible for defendants with legitimate claims to obtain the evidence necessary to support them, we sought a middle ground in Bourgeois. See Bourgeois, 964 F.2d at 938-39. We settled on a “colorable basis” standard:
[T]o obtain discovery on a selective prosecution claim, a defendant must present specific facts, not mere allegations, which establish a colorable basis of both discriminatory application of a law and discriminatory intent on the part of government actors.
Id. at 939.
Although we described the Bourgeois stán-dard as establishing a “high threshold,” id., it is clear that under that test a defendant need not come anywhere close to proving a claim of selective prosecution in order to obtain discovery. Indeed, the defendant need not even present a prima facie case. The defendant instead need only present “some evidence tending to show the essential elements of the claim.” United States v. Heidecke, 900 F.2d 1155, 1159 (7th Cir.1990) (discussing “colorable basis” standard). While a defendant will not satisfy his burden by merely presenting unsubstantiated or generalized allegations, he is entitled to discovery if he can show some specific facts which raise an inference of impermissible discrimination.3
Under the Bourgeois standard, the defendants have presented more than enough evidence to' raise a sufficient inference of discrimination to warrant discovery. In particular, the study conducted by the Office of the Federal Public Defender raises a strong inference of invidious discrimination. This study found that, of all cocaine base cases closed by the Office in 1991, 24 out of 24 involved black defendants. To be sure, such a small sample does not conclusively establish either of the elements of selective prosecution. However, the fact that every single crack defendant represented by the Federal Public Defender in a case that terminated during 1991 was black certainly raises enough of a question to justify further inquiry by the court.
The evidence supporting an inference of discriminatory prosecution in this case is much stronger than the evidence we held insufficient to justify discovery in Bourgeois. In that case, the defendants argued that they were entitled to discovery based on a showing that all prosecutions for firearms violations stemming from a two-day police operation involved black defendants. The district court rejected the defendants’ claims, holding that two days was far too short a period to serve as a basis for analyzing the overall conduct of a prosecutorial agency. Instead of focusing on the single operation which *1442resulted in the arrests of Bourgeois and his associates, the district court looked instead to all firearms prosecutions over a two-year span. The court found that the government had prosecuted over 140 people during that period for the same crimes as those for which Bourgeois was prosecuted. Because Bourgeois “did not allege that all or most of these cases involved blacks,” Bourgeois, 964 F.2d at 940, the district court concluded that he had not established a colorable basis, to justify discovery. We held that the district court did not abuse its discretion in refusing to order discovery in these circumstances. See id. at 941.4
The evidence offered in Bourgeois involved only one operation, over a single two-day period. The Federal Public Defender study, by contrast, involved an agency that represents a significant percentage of all federal criminal defendants, and it involved all cases closed over a significant period of time. Common sense indicates that the inference of discrimination one can reasonably draw from such a study is much stronger than the inference one can draw from evidence involving only a single, short police operation. See. id. at 941 (“[T]he relevant inquiry is the history of prosecutions over a reasonable period of time.”). The study showed that the largest single provider of legal services to federal criminal defendants in the Central District of California did not conclude a single crack defense of a non-black defendant in all of 1991. Although the sample size is too small to resolve the issue either way, this evidence certainly raises a serious question whether the government is intentionally discriminating against blacks. I do not see how the majority can conclude that it .was an abuse of discretion for the district court to allow the defendants to inquire further into the issue.
The majority concludes that the Federal Public Defender study is insufficient to warrant discovery because it “demonstrates only that others have been prosecuted, not that others similarly situated have not.” Ante at 1436. Yet even by the majority’s own standard a defendant is not required to demonstrate that the government has failed to prosecute others who are similarly situated. He need only “provide a colorable basis for believing that others similarly situated have not been prosecuted.” Ante at 1436 (emphasis ádded). The study introduced by the defendants clearly satisfies this requirement. Given the prevalence of all kinds of drugs throughout our community, at least some crack distributors must be- non-blacks. The fact that the Office of the Federal Public Defender had not closed a ease involving a single non-black defendant in an entire year provides at least a colorable basis to believe that some non-black offenders existed whom *1443the United States Attorney failed to prosecute.
When a defendant presents statistics tending to show that all prosecutions over a significant period of time are directed at members of a single race, such a presentation alone should raise sufficient suspicion to warrant a further-inquiry. On closer scrutiny, we may discover that the statistics can be explained by methodological defects, such as an inadequate sample size or an insufficient time-frame. However, one fact we most assuredly will never find. If our method of analysis is at all fair or rational, we will not discover that it is only members of the defendant’s race who commit the crime in question.
Contrary to the majority’s view, we must assume, what is unquestionably the case, that people of all races commit all types of crimes. Under no circumstances can 'we base our analysis on the premise that any type of crime may be the exclusive province of any particular racial or ethnic group. Yet that is precisely what the majority does.Even if the defendants made a conclusive showing that the government had only prosecuted members of a single race for a particular class of crime, the majority would apparently conclude that they had failed to meet their burden. My colleagues would apparently require the defendants to present affirmative evidence showing that similarly situated potential defendants of other races existed — in other words that whites and browns also commit violations of 21 U.S.C. §§ 841 and 846. See ante at 1486 (“The first affidavit demonstrates only that' others have been prosecuted, not that others similarly situated have not — obviously, a total lack of evidence cannot constitute a colorable basis for believing that discriminatory application of the law exists.”). Unless we make the unsupportable assumption that there is a reasonable possibility that only blacks commit the crimes with which the defendants are charged, the majority’s analysis is manifestly erroneous. If the United States Attorney’s office prosecutes only members of a particular race, simple logic and common sense tell us that.it is failing to prosecute at least some similarly-situated members of other races. Where a defendant shows a reasonable statistical basis for the inference that all defendants charged with a particular federal crime over a significant period of time were members of a single race, such a showing creates, ipso facto, a colorable basis for believing that similarly situated members of other races were not prosecuted. Therefore, there is no legal basis whatsoever for requiring the defendant to point to particular cases in which the government failed to prosecute similarly-situated members of other races.
The majority rightly notes that the Federal Public Defender study does not in itself establish that the United States Attorney has engaged in selective prosecution. It is true that the study refers only to cases closed in 1991 and that it fails to provide more detailed information regarding the specifics of the offenses the other defendants allegedly committed. It is also true that the study does not disclose whether any non-black defendants existed who could afford to hire then-own attorneys. See Ante at 1436-87. While these aspects of the study render it insufficient to support an ultimate showing of unconstitutional selective prosecution, the facts set forth are nonetheless more than enough to support a finding of a colorable basis for the claim that discrimination exists. Despite the limitations in-the study’s methodology, it is sufficient to lead a reasonable person to believe that the United States Attorney might be engaging in discrimination and that further inquiry on the subject is warranted. That is precisely the course the district court took here, and I do not believe that it abused its discretion in doing so.
Although the Federal Public Defender study should have been enough to create a colorable basis, the defendants here did provide additional evidence that the federal government failed to prosecute similarly-situated non-black defendants. On the government’s motion for reconsideration, the defendants introduced two affidavits from different defense attorneys. One related a statement made by an intake coordinator at a Pasadena halfway house who said that, in his experience, there were an equal number of white and non-white users and dealers of crack. The other affidavit came from David R. *1444Reed, an experienced criminal defense attorney in the Central District. Reed stated that, in his experience as a federal criminal defense lawyer and as a director of the state court indigent defense panel, he had never handled, known of, or heard of a single federal crack cocaine case involving non-black defendants, but that he knew of many crack cocaine cases prosecuted against non-blacks in state court.
My colleagues wholly discount these affidavits. Their analysis is flawed in two separate respects, however. First, they seem to believe that the affidavits must be considered in isolation, rather than in light of the Federal Public Defender Study. They criticize the district court for “placing any weight” on the first affidavit, ante at 1437-38, and they state that the second affidavit failed to contain “the ‘specific facts, not mere allegations, which establish a colorable basis for the existence of ... discriminatory application of a law.’ ” Ante at 1437-38 (quoting Bourgeois, 964 F.2d at 939). Whether or not it would have been appropriate for the district court to place any weight on the declarations if they stood alone, they surely satisfy the defendants’ burden when considered in light of the study’s finding that all federal crack defendants were black. When all of this evidence is taken together, the defendants have established several “specific facts, not mere allegations, which establish a colorable basis” to believe that the government has engaged in selective prosecution: (1) in all crack cocaine cases closed by the Federal Public Defender’s Office in 1991, not a single case involved a non-black defendant; (2) an individual with professional experience in treating cocaine base addicts was of the opinion that minorities and non-minorities used and dealt crack in roughly equal numbers; (3) a criminal defense lawyer experienced in defending individuals in federal court, and overseeing indigent defense in state court, had knowledge of many non-black crack offenders who were prosecuted in state court, but none who were prosecuted in federal court.
Second, the majority appears to ignore the fact that the defendants are only seeking discovery on their selective prosecution claim. The defendant’s burden in seeking discovery is obviously significantly less than the defendant’s ultimate burden of proving that the government engaged in discriminatory prosecution. Under Bourgeois, a defendant need not even present a prima facie case in order to obtain discovery, only a colorable basis. See Bourgeois, 964 F.2d at 939. There is no reason to require the defendant to produce admissible evidence in making such a showing.5 In other contexts in which a party bears a lighter burden of proof than a preponderance of the evidence, the law has held that the lesser quantum of evidence required also entails looser requirements regarding the admissibility of that evidence. See, e.g., Costello v. United States, 350 U.S. 359, 76 S.Ct. 406, 100 L.Ed. 397 (1956) (grand jury); United States v. One 56-Foot Motor Yacht Named the Tahuna, 702 F.2d 1276, 1283 (9th Cir.1983) (probable cause for forfeiture); Fed.R.Crim.P. 5.1(a) (preliminary probable cause hearing). That rule is applicable here as well. The majority thus errs in dismissing the declarations as hearsay.
The majority also errs by appearing to require the defendants to substantiate their claims more fully at this stage of the proceedings than is necessary under Bourgeois. In order to obtain discovery, defendants should not be required to present sophisticated regression analyses closely following the dictates of the scientific method. Nor should they be required to compile facts which are not readily available to them, such as the racial breakdown and offense characteristics of defendants represented by other counsel. Instead, they should only be required to show that specific facts raise a strong inference of impermissible discrimination, and they should only be expected to use whatever evidence is within their possession or reason*1445ably obtainable. The defendants here have satisfied that burden.6
IV.
As I explained above, the majority’s opinion leaves Judge Marshall free on remand to impose the same discovery order as she had before, so long as she explains that she is basing her order in part on her personal observations of and experience with the United States Attorney’s office. In addition, even disregarding that factor, it appears that a sufficient factual basis now exists to satisfy even the majority’s overly restrictive application of our standards. A study by Richard Berk of the Center for the Study of the Environment and Society of the University of California at Los Angeles demonstrates that the United States Attorney has failed to prosecute similarly situated white offenders. See Richard Berk and Alec Campbell, Preliminary Data on Race and Crack Charging Practices in Los Angeles, 6 Fed.Sentencing Rep. 36 (1993). Although this study was not before the district court, and thus is not part of the record we review, it provides further indication that the majority has erred in disregarding the evidence that is before it and in overturning the district court’s order.7 If the defendants renew their motion on remand and introduce this study as evidence, the district court would clearly be justified— even without considering its own experience — in reinstating the discovery order.
The Berk study analyzed both state and federal data concerning crack cocaine offenses in the Los Angeles area. Specifically, it analyzed all arrests for sale of cocaine base within Los Angeles County between January 1, 1990 and October 10, 1992, all cases referred to the Los Angeles County District Attorney for sale of cocaine base between January 1, 1990 and August 11, 1992, and all sale of cocaine base cases prosecuted by the United States Attorney for the Central District of California between 1988 and 1992. See id. at 36.
Analyzing these data, the Berk study reached some alarming conclusions, which are consistent with the defendants’ position here.8 Like the Federal Public Defender study, the Berk study found that, over a nearly two-year period, the United States Attorney did not charge even a single white person with sale of crack cocaine. By analyzing state data, however, the Berk study also refuted the majority’s implicit assumption that non-blacks simply do not commit these crimes. Indeed, the data showed that the Los Angeles County District Attorney charged over two hundred whites with sale of cocaine base during this period.
The Berk study’s conclusions strongly suggest that the United States Attorney’s office has engaged in discriminatory prosecution. Although only 58 per cent of the arrests in Los Angeles County for sale of crack during the study’s time period involved blacks, and *1446only 53 per cent of crack sale charges by the Los Angeles County District Attorney involved black defendants, the United States Attorney targeted black defendants a full 88 per cent of the time. The disparity between the state and federal figures would seem to necessitate a further investigation of the reasons for the differing actions by the two prosecutorial agencies. In conducting his study, Professor Berk performed chi-squared tests to determine whether the results of his statistical survey could be attributed to chance rather than discrimination. He found that “[f]or the federal data, the chances are less than 1 in 100 (p-value = .0088) that they are just a ‘luck of the draw’ sample for the population of people arrested.” Id. at 38.
The Berk study, as well as the data proffered by the defendants in this ease, is sufficient to raise a serious question about whether the United States Attorney’s office is treating all of the people it serves equally. In particular, it raises the question of whether the United States Attorney reserves the ten-year federal mandatory minimum sentences for black defendants, while allowing non-black defendants to receive three, four, or five year sentences in state court. We cannot tolerate basing the length of a sentence on the color of a defendant’s skin. Where there is a colorable showing that this may be occurring, an inquiry is required.
Y.
As a practical matter, as I have pointed out, the majority’s opinion will have little or no effect on the further proceedings in the district court. The Berk study, which was not before the court when it made its discovery order here, will certainly provide enough of an additional “colorable basis” to support discovery if and when the defendants file a renewed or amended motion following remand. So, too, will the personal knowledge and experience that the majority finds Judge Marshall failed to avail herself of the first time.
Nonetheless, it is most unfortunate that the majority overrules Judge Marshall’s considered attempt to gain more information about the United States Attorney’s charging practices. The five to seven year difference between state and federal sentences for crack sale offenses is not merely academic— five years is a long time to spend in prison. As long as this disparity exists, federal courts have an obligation to make sure that the United States Attorney is treating all members of the community fairly and equally-
Judge Marshall’s actions showed the judiciary at its best. Unlike the majority, I would not be so quick to overrule her attempt to explore this critical issue and to get more objective information before the court. Certainly, there is no basis whatsoever for concluding that Judge Marshall abused her discretion in trying to do so and in determining that the defendants made a colorable showing of discriminatory enforcement of the law.
Judge Marshall acted properly by ordering discovery with respect to this issue. I would affirm.
. Unlike the majority, I see no practical difference between Bourgeois's "colorable basis” test and the "reasonable inference” test which Re-dondo-Lemos requires be used when a party offers evidence tending to establish selective prosecution. There is nothing in these phrases or in the courts’ analysis in Bourgeois and Redondo-Lemos to suggest any difference between these standards. (Nor, incidentally, does the majority explain how they differ).
I note that the majority's recitation of the framework set forth in Redondo-Lemos is somewhat misleading. The majority states that Re-dondo-Lemos does not "raise[] the possibility of discovery by the defense” until after the defendant has presented evidence creating a "reasonable inference” of discrimination and the prosecution has had an opportunity to rebut this showing. Ante at 1435. The majority ignores footnote 12 of Redondo-Icemos, which clearly contemplates "limited discovery in appropriate circumstances prior to the prosecutor’s evidentiary presentation.” Redondo-Lemos, 955 F.2d at 1302 n. 12.
. For example, in ordering discovery, the district judge stated:
*1441That is the problem I think that needs to be addressed, because we do see a lot of the cases and one does ask why some are in state court and some are being prosecuted in Federal court, and if it's not based on race what's it based on?
. Thus, the Bourgeois court's prediction that only a small number of defendants would be able to make a sufficient showing to obtain discovery was just that — a prediction. It provides no basis for artificially raising the standard which defendants must meet in order to gather more information on their discriminatory prosecution claims.
. By lifting a sentence out of context and then misreading it, the majority unintentionally distorts our decision in Bourgeois. The majority states:
The court in Bourgeois found that Bourgeois had failed to establish a colorable basis that others similarly situated had not been prosecuted. It did this because “Bourgeois [made] no attempt to show that, in any span of time, the government has declined to prosecute similarly situated, non-black felons illegally in possession of firearms.” Thus, the court explained that regardless of the duration of the operation in question, defendants attempting to obtain discovery on a claim of selective enforcement must provide a colorable basis for believing that similarly situated felons not in their protected class were passed over for prosecution. The evidence in this case was unsatisfactory for the very same reason, and the duration of the operation in each case therefore irrelevant.
Ante at 1438 (citations omitted) (emphasis in majority opinion).
Contrary to the majority's understanding, the issue in Bourgeois was precisely whether the defendants had shown discrimination over a sufficient period of time. The Bourgeois court assumed that, during the two-day period in question, the government had prosecuted only blacks and had failed to prosecute similarly situated non-blacks. However, it held that a two-day focus was too narrow: "The government need not provide discovery on a selective prosecution claim simply because law enforcement officials focused for a short time on a racially homogeneous criminal group." Bourgeois, 964 F.2d at 940-41. The sentence immediately preceding the one the majority selectively quotes states that “[a]s discussed above, the relevant inquiry is the history of prosecutions over a reasonable period of time.” Id. at 941. In this context, the Bourgeois court’s statement that "Bourgeois makes no attempt to show that, in any span of time, the government has failed to prosecute similarly situated, non-black felons illegally in possession of firearms” simply refers to the defendants’ failure to make a showing of discrimination across a "span of time."
. I should emphasize that the Federal Public Defender study was clearly admissible, and, in my view, it was sufficient in itself to create a colorable basis. The majority only challenges the admissibility of the two declarations. In this connection, I should note that any objection as to admissibility must be raised in the district court and that no such objection was made here. .
.I should note that nearly all of the data necessary to a showing of selective prosecution are far less accessible to the defendants than to the federal government. Federal and county law enforcement authorities cooperate closely in these cases, and both levels of government are involved in the decision whether to bring charges in federal or state court. The Assistant United States Attorney admitted as much before the district court. He stated that many cocaine base cases were investigated as part of a joint federal/state task force involving local police departments and the federal Bureau of Alcohol, Tobacco, and Firearms. Given that the federal and local authorities work so closely in investigating these crimes, the federal government probably already has records of the cases in which it declined to initiate a federal prosecution. In any event, it is surely much easier for the United States Attorney’s office to get this information from state officials, from the county prosecutor's offices, and from local police departments than it is for criminal defense lawyers. Federal, state, and local law enforcement authorities have a cooperative relationship; prosecutors and defense lawyers have an adversarial relationship. Especially since the pertinent records relating to cases in the geographical area covered by the Central District may well be scattered across seven different county district attorney’s offices, seven separate sheriff's departments, and a large number of independent local police departments, the defendants would have an almost impossible time compiling data on their own.
. We may take judicial notice of this published study on appeal. See Brown v. Board of Education, 347 U.S. 483, 494 n. 11, 74 S.Ct. 686, 692 n. 11, 98 L.Ed. 873 (1954); Swan v. Peterson, 6 F.3d 1373 n. 9 (9th Cir.1993).
. The statistical conclusions of the Berk study are summarized on page 37.