The opinion of the court was delivered by: Colleen Kollar-kotelly United States District Judge
Currently before the Court are several filings by the parties that relate to the Government's planned use of certain DeoxyriboNucleic Acid ("DNA") evidence in the trial. Specifically, the Court is confronted with: (1) Defendants' Joint Objections to the Government's Proposed DNA Evidence, filed on April 5, 2005; (2) Government's Opposition to Defendants' Joint Objection to the Government's Proposed DNA Evidence, filed on April 8, 2005; (3) Government's Supplemental Opposition to Defendants' Joint Objection to the Government's Proposed DNA Evidence, filed on April 11, 2005; (4) Defendant Malvin Palmer's Response to Government's DNA Pleadings, filed on April 13, 2005; (5) Defendant Miquel Morrow's Reply to the Government's Supplemental Opposition to the Defendant's Joint Objections to the Government's Proposed DNA Evidence, filed on April 14, 2005; and (6) Government's Reply to Defendant Palmer's and Morrow's Responses to the Government's Proposed DNA Evidence, filed on April 14, 2005.
These filings deal to a substantial degree with a question posed by the Court in an April 7, 2005 Scheduling Order. See United States v. Morrow, Crim. No. 04-355 (D.D.C. Apr. 7, 2005) (scheduling order re: DNA evidence). In relevant part, the Court ordered legal briefing addressing two major issues:
(1) whether the Government, in its direct case, may pro-actively present, through an expert, scientific evidence that does not conclusively identify a defendant, but also does not exclude a defendant as a possible match; and (2) whether the Government, if it cannot present such evidence in its direct case, may bring out such information during cross-examination or re-direct if the defense has opened the door by affirmatively arguing that the scientific evidence exonerates or provides no link to the defendants.
Id. at *1. Central to the Court's concerns was the impact of the Supreme Court's decision in Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993), on DNA match probability data. Specifically, the Court was interested in the admissibility of DNA match probability information that fell below a certain level of statistical significance. In making this inquiry, the Court sought to establish the broad parameters for DNA evidence admission in the upcoming trial; it did not seek to make a final ruling concerning the admissibility of all DNA evidence. Upon a review of the legal briefing, some of the statistical probabilities involved in this case, and the relevant case law, the Court concludes that DNA evidence indicating a relatively low match probability significance may be introduced in the Government's presentation of its direct evidence, subject to certain parameters and restrictions.
On November 9, 2004, the Grand Jury in the above-captioned case returned a twenty-one count Superseding Indictment against the six remaining defendants in this case -- Miquel Morrow, Lionel Stoddard, Carlos Aguiar, Bryan Burwell, Aaron Perkins, and Malvin Palmer (collectively, "Defendants").*fn1 Count I of the Indictment charges all six Defendants with a conspiracy to participate in a Racketeer Influenced Corrupt Organization ("RICO"), in violation of 18 U.S.C. § 1962(d), based upon alleged racketeering acts involving armed robberies of four banks in the District of Columbia (Acts 1-4) and two banks in the District of Maryland (Acts 5-6), as well as three acts involving murder (Acts 7-9). Count II charges all six Defendants with a conspiracy to commit offenses against the United States. Substantive charges involving armed bank robbery (Counts III, VIII, XII, and XVII), using or carrying a firearm during a crime of violence (Counts IV, IX, XIII, XVIII), unlawful possession of a firearm by a felon (Counts VVII, X-XI, XIV-XVI, XIX), and assault with intent to kill (Counts XX-XXI), are charged against the specific defendants named in those counts. The armed robberies were allegedly accomplished while the Defendants brandished weapons and wore body armor, hoods, masks, bandanas, and heavy clothing to avoid identification. The assaults also involved the use of firearms.
As part of the planned prosecution of Defendants, the Government intends on introducing expert testimony connecting the DNA of certain defendants with DNA material left on specific items of evidence. See Gov'ts Notice of Intention to Introduce Expert Testimony; Gov'ts Suppl. Opp'n at 1. In January 2005, the Government submitted a large volume of DNA discovery materials to defense experts, including the results of testing done at the FBI Laboratory for DNA evidence. Gov'ts Opp'n at 1. As noted in the DNA discovery materials, the FBI Laboratory used the Polmerase Chain Reaction ("PCR") amplification method and analysis of Short Tandem Repeats ("STR") to test DNA samples in this case. Gov'ts Suppl. Opp'n at 2. To enable a fact-finder to understand the significance of the results, the FBI also calculated the coincidental, or "random match," probabilities that the DNA profile in the evidence sample would be found at random in the population based on population frequency data for four population groups -- that is, African-American, Caucasian, Southeastern Hispanic, and Southwestern Hispanic population groups. Id.
Each defendant in this case has a separate DNA expert, save for Defendants Perkins and Palmer, who share an expert. After the Government submitted its DNA discovery materials, these defense experts then conducted a review of the Government's DNA discovery. Upon such a review, Defendants have argued that "it is clear that some of the government's proffered DNA reports are of marginal statistical significance." Defs.' Joint Objections at 1, ¶ 2.
In response, the Government explains that its various DNA reports "showed varying results for different items, from the conclusion that a specific defendant was the contributor of a sample to the conclusion that a respective defendant could or could not be excluded as a potential contributor." Gov'ts Opp'n at 1. According to the Government, "[t]he items to which defendant Morrow appears to be objecting, see Defendants' Motion, ¶ 3, are those items where defendant could not be excluded as a potential contributor." Id. Going into more detail in its Supplemental Opposition, the Government notes that it has obtained DNA evidence in this case that shows a spectrum of five different kinds of results. Gov'ts Suppl. Opp'n at 2. These results range from:
(1) to a reasonable degree of scientific certainty, defendant was the contributor of the sample; (2) defendant is potentially the major contributor in a mixed sample, e.g., DNA from more than one individual; (3) defendant cannot be excluded as a potential contributor of the sample; (4) defendant cannot be excluded as potential major or minor contributor in a mixed sample; and (5) defendant was excluded as a potential contributor of the sample.
Id. at 2-3. When there was a "positive result," i.e., when a DNA sample fit into categories 1-4, the FBI Laboratory's report provides a statistical estimate of the probability of selecting an unrelated individual at random from the four population groups that would have the same DNA profile as observed in the item of evidence at issue. Id. at 3. According to the Government, "[t]hese numbers range from 1 in 280 billion for the conclusion that the defendant was the contributor, to such numbers ranging from as high as 1 in 16 billion to lower ratios such as 1 in 2,400 where a defendant is potentially a major contributor in a mixed sample, to such numbers as 1 in 20, or even as low as 1 in 1, where a defendant cannot be excluded as a contributor of a sample." Id. The Government emphasizes that it does not intend to discuss any instances where a defendant could not be excluded as a potential contributor in its opening statement, but that it intends to introduce such evidence at a later point. See Gov'ts Resp. to Def. Palmer's and Def. Morrow's Resps. at 2.
Specifically, Defendant Morrow objects to the admission of four DNA samples: (1) Q62, which apparently shows that Defendants Morrow and Perkins cannot be excluded as potential contributors, although the probability of selecting an unrelated individual is 1:3 in the African-American population; (2) Q219, which shows that Defendants Morrow, Palmer, and Burwell cannot be excluded, although the probability of selecting an unrelated individual is 1:6 in the African-American population; (3) Q279, which shows that Defendant Morrow cannot be excluded, although the probability of selecting an unrelated individual is 1:12 in the African-American population; and (4) K5, which shows that Defendant Morrow cannot be excluded, although the probability of selecting an unrelated individual is 1:1 in all populations. See Def. Morrow's Reply at 1, ¶ 1. At this time, Defendant Palmer also objects to the admission of three DNA samples: (1) Q219, as noted above in Defendant Morrow's objections; (2) Q319, which apparently indicates presence of DNA from more than one individual, including possibly Defendant Palmer, although the probability of selecting an unrelated individual is 1:7 in the African-American population; and (3) Q104, which indicates the presence of DNA from more than one individual, including possibly Defendants Palmer and Perkins, who cannot be excluded as potential contributors to the mixture, although the probability of selecting an unrelated individual is 1:7 from the African-American population. Def. Palmer's Resp. at 4, ¶ 10. In addition, Defendant Palmer objects to "being included in the 'African-American' population of the United States since he is Jamaican by birth and does not share the population genetics characteristics of African-Americans." Id. at 1-2, ¶ 3. In response, the Government notes that the FBI Laboratory will "also run the samples found that matched for defendant Palmer using the [sic] a Caribbean population group data base, which includes individuals from Jamaica, Trinidad and the Bahamas." Gov'ts Reply to Def. Palmer's and Def. Morrow's Resps. at 1-2. According to the Government, the results from this comparison should "be done within a couple of weeks, but that the resulting ratios would be somewhat similar." Id. at 2.
Two central issues are before the Court, and an investigation of each is necessary to answer the questions posed by this Court in its April 7, 2005 Scheduling Order. First, the Court must analyze whether the Government's PCR amplification method and STR analysis to test DNA samples in this case comports with the requirements concerning expert scientific testimony laid down by the Supreme Court in Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993), and Kumho Tire Co. v. Carmichael, 526 U.S. 137, 119 S.Ct. 1167, 143 L.Ed.2d 238 (1999). Second, the Court must examine whether DNA evidence indicating a relatively low level of statistical significance should be excluded from either direct presentation or introduction on cross-examination under either the principles inherent in Daubert or Federal Rule of Evidence 403, which excludes relevant evidence when its "probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by considerations of undue delay, waste of time, or needless presentation of cumulative evidence." Fed. R. Evid. 403. The Court shall conduct an inquiry into each issue in sequence.
A. The Use of the PCR/STR DNA Methodology Comports With the Requirements of Daubert
The specific DNA methodologies employed by the Government in this case -- using the PCR amplification method coupled with STR analysis to test available DNA samples -- have been extant for over a decade, and are widely used in criminal cases. In order to determine whether the Court even needs to conduct an analysis of the admissibility of DNA evidence with a low statistical significance, the Court must first determine the threshold question of whether the Government's PCR/STR methodology, as a general rule, meets the requirements of Daubert. As such, the Court shall (1) conduct a brief overview of the DNA typing methodology at issue in this case, and (2) then proceed to examine the general acceptance of the methodology in various jurisdictions.
DNA, an acronym for DeoxyriboNucleic Acid, is the chemical blueprint for life. Most human cells, other than reproductive cells, contain identical copies of a person's DNA. Although 99.9% does not vary from person to person, no two persons other than identical twins have the same DNA. See National Research Council, The Evaluation of Forensic DNA Evidence 63 (1996) ("NRC II"); United States v. Shea, 957 F. Supp. 331, 333 (D.N.H. 1997), aff'd, 159 F.3d 37 (1998), cert. denied, 526 U.S. 1077, 119 S.Ct. 1480, 143 L.Ed.2d 563 (1999).*fn2
Human DNA is organized into 23 pairs of chromosomes and each chromosome contains a DNA molecule. DNA molecules have a classic double-stranded helical structure that can be envisioned as a spiral staircase. See National Research Council, DNA Technology in Forensic Science 2 (1992) ("NRC I"). Running between the two sugar-phosphate strands forming the handrails of the staircase are millions of steps comprised of two loosely bound nitrogen bases. Each step is referred to as a "base pair." There are four types of bases: adenine (A), thymine (T), guanine (G), and cytosine (C). A's ordinarily pair only with T's, and C's ordinarily pair only with G's. As such, if the sequence of bases on one side of the DNA molecule is known, the corresponding sequence of bases on the other side can be deduced. Importantly, the actual ...