Full opinion text
MEMORANDUM OPINION JOSÉ ANTONIO FUSTÉ, District Judge. This matter comes before the court as a pre-trial determination whether the Defendant, Alexis Candelario-Santana (“Defendant” or “Candelario-Santana”), is mentally retarded for the purposes of Atkins v. Virginia, 536 U.S. 304, 122 S.Ct. 2242, 153 L.Ed.2d 335 (2002), and the Federal Death Penalty Act, 18 U.S.C. § 3596(c). The court held three days of evidentiary hearings on this matter, on December 6, 7, and 21. Having carefully considered the parties’ arguments, the evidence before us, and the pertinent case law, this court now issues its opinion. I. Introduction A. Standards and Burden of Proof for Pre-Trial Determination The government has notified the parties of its intent to seek the death penalty in this case. (Docket No. 458.) CandelarioSantana argues that because he is mentally retarded, the government cannot seek the death penalty. (Docket No. 564 at 140-145.) Both parties agree that the Defendant bears the burden of proof on this issue by a preponderance of the evidence, and that logically, the issue should be resolved, before trial begins. Every district court that has addressed the issue that we are aware of has held the same. See, e.g., United States v. Smith, 790 F.Supp.2d 482, 484 (E.D.La.2011) (allocating burden of proof to defendant by preponderance of the evidence standard and resolving before trial); United States v. Sablan, 461 F.Supp.2d 1239, 1242 (D.Colo.2006) (establishing same burden of proof and ruling that determination be made before trial). B. Definitions of Mental Retardation In Atkins, the Supreme Court held that execution of mentally retarded persons violates the Eighth Amendment’s prohibition of “cruel and unusual punishments.” 536 U.S. at 311, 316-21, 122 S.Ct. 2242 (quoting U.S. Const. Amend. VIII). The Court twice discussed clinical definitions of mental retardation, see id. at 308 n. 3, 318, 122 S.Ct. 2242, but did not provide a definition. Id. at 317, 122 S.Ct. 2242. After surveying a recent history of executions, the Court held that a national consensus had developed against executing persons with a “known IQ less than 70,” a practice that had become “truly unusual.” Id. at 316, 122 S.Ct. 2242. The Court acknowledged that “[n]ot all people who claim to be mentally retarded will be so impaired as to fall within the range of mentally retarded offenders about whom there is a national consensus.” 536 U.S. at 317, 122 S.Ct. 2242. The Court therefore left “to the States the task of developing appropriate ways to enforce the constitutional restriction upon their execution of sentences.” Id. (quoting Ford v. Wainwright, 477 U.S. 399,106 S.Ct. 2595, 91 L.Ed.2d 335 (1986)). The Court also cited a clinical definition of “mild” mental retardation, a condition “typically used to describe persons with an IQ between 50-55 and approximately 70.” Id. at 308 n. 3, 122 S.Ct. 2242 (citing American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders: DSM-IV 42-43 (4th ed.2000) (hereinafter DSM-IV)). In discussing two “similar” definitions provided by the American Association on Mental Retardation (“AAMR”) and the American Psychiatric Association (“APA”), the Court noted that “clinical definitions of mental retardation require not only subaverage intellectual functioning, but also significant limitations in adaptive skills such as communication, self-care, and self-direction that became manifest before age 18.” Id. at 318, 122 S.Ct. 2242. When asked in court, both parties agreed that an individual must meet each of these three prongs in order to be considered mentally retarded. We agree. It is important to note that while “the Supreme Court in Atkins could have adopted the clinical standard” for defining and evaluating mental retardation, “it explicitly declined to do so.” Hooks v. Workman, 689 F.3d 1148, 1168 (10th Cir.2012). Thus, our analysis need not rigidly adhere to the clinical standards. Though the clinical standards have informed our analysis, we emphasize that “a clinical standard is not a constitutional command.” Id. In evaluating Defendant’s claim, therefore, we have taken our primary guidance from Supreme Court precedent in Atkins and helpful expert testimony. After extensive deliberation, and for the reasons explained below, we conclude that Candelario-Santana is not mentally retarded. II. Candelario-Santana’s Background Candelario-Santana is a forty-one year old male from Puerto Rico. The following background, unless otherwise noted, is derived from pages seven through twelve of the report by Dr. María T. Margarida Juliá (“Dr. Margarida”). Candelario-Santana was the fourth of eleven children born to his mother, Adelaida Santana Pinto, who produced children from five different unions. Candelario-Santana’s father, Hipólito Candelario-Santana, abandoned Candelario-Santana’s mother when Defendant was very young, and had very little contact with him. When Candelario-Santana was twelve years old, his mother sent him to Florida to live with his father, but Candelario-Santana soon returned home to Puerto Rico, because he and his father did not get along. Candelario-Santana had very little contact with his father after that. Candelario-Santana was raised in Barrio Sabana Seca, in Toa Baja, in an area known as “The Mangos.” The neighborhood he grew up in was filled with violence, drug sales, and frequent shootings. At one point, Candelario-Santana watched his uncle, Jorge, die after being shot in a dispute over a watch. The police would frequently enter the home where Candelario-Santana grew up, searching for fugitives. The home where Candelario-Santana and his siblings lived was a two-bedroom dilapidated house made out of wood. The house was located in a larger plot of land owned by Candelario-Santana’s aunt. The aunt lived in a larger house on the same plot of land. Conditions in Candelario-Santana’s house were very poor; he says that his family suffered from hunger. There are very few school records available from Candelario-Santana’s childhood. Candelario-Santana apparently told Dr. Margarida that he dropped out of school in the seventh grade, because of his frustrations as a “slow learner.” In his interview with the government’s experts, Dr. Jaime Herrera Pino (“Dr. Herrera”), and Dr. Jaime Grodzinski Schwartz (“Dr. Grodzinski”), Candelario-Santana provided an additional explanation for his decision to drop out, which was his desire to work and help his mother overcome their family’s poverty. Later during the hearing, the court saw a diploma indicating that Candelario-Santana had finished the ninth grade. The few available records suggest that Candelario-Santana likely repeated one grade in school, though it is unclear which grade, or the reasons behind that circumstance. There are also several indications that Candelario-Santana never applied himself in school. He told Dr. Zahira Lespier Torres (“Dr. Torres”), a psychologist who interviewed him in 2008, that he used to “cut classes.” Candelario-Santana admitted to Dr. Herrera that he was often reprimanded for misbehaving and asked to leave the classroom. Candelario-Santana also indicated to Dr. Herrera that he often behaved in ways that were distracting to other students in the class. To Dr. Grodzinski, Candelario-Santana admitted that his economic and family worries were continuously distracting him from his studies and that his school attendance dropped because of family-related concerns. He also told Dr. Grodzinski that he liked to learn Spanish and Science. CandelarioSantana told Dr. Grodzinski that despite his family’s poverty, he remembers being playful, having a lot of fun going out with friends, and enjoying fighting other kids in his neighborhood. At some point between the ages of fifteen and seventeen years old, CandelarioSantana moved to New York. While in New York, he worked for one year in a full-time job at a factory. His sister Mildred worked at the same factory. After a year, he returned to Puerto Rico. In addition to his job in the factory, Candelario-Santana has had an assortment of other part-time jobs, including working in construction, where he earned $120 per week after dropping out of the seventh grade; landscaping, when he lived in Detroit; performing odd jobs at stables, where he took care of horses for three years; and driving a truck to transport merchandise. On one occasion, Candelario-Santana was able to save enough money to buy his own truck. When he was twenty-two years old, Candelario-Santana obtained a driver’s license, which he still has. Though he has had no formal training, Candelario-Santana says he knows how to fix a car and change filters and brake pads. At some point, he also received a license to operate heavy equipment. Candelario-Santana also stated that between the ages of eleven and thirty-eight years, he enjoyed boxing and would sometimes train every day. Even though he used protection, Candelario-Santana says that he received several head concussions during training and fights. He estimates that he suffered approximately ten to twenty concussions, which caused an altered state of consciousness and brief confusion. Also, when Candelario-Santana was twenty years old, he suffered a head injury in a motorcycle accident in which he claims to have temporarily lost consciousness. Upon regaining consciousness, he rode his motorcycle home. There are no medical records available regarding the injury. While the exact chronology is unclear, Candelario-Santana has moved to and from Florida; Puerto Rico; Brooklyn, New York; and Detroit, Michigan, throughout his life. For most of his life, Candelario-Santana has lived either with his relatives or the mothers of his children. Candelario-Santana has five children from two different unions. When he was sixteen or seventeen years old, Candelario-Santana married Sonia Benitez, with whom he has two children, now twenty-three and twenty-two years old. His second relationship with Isabel Ocasio produced three more children, all of whom live in Detroit. Individuals who know Candelario-Santana indicate that he is “a good father as far as people can tell.” This court also received information from pretrial services regarding Candelario-Santana’s criminal background. We have seen reports of Defendant’s history from the National Crime Intelligence Center (NCIC), as well as the original conviction records from Puerto Rico’s commonwealth courts. In addition, a criminal history analysis, dated December 6, 2012, and provided by the Puerto Rico Police Department, confirmed that Defendant has been adjudged guilty of twelve murders. Defendant also has several more felony convictions on his record, including for firearms violations and destruction of evidence. During the hearing, the government and a defense witness agreed that Defendant had been convicted of “some sixty felonies.” The list of convictions and brushes with the criminal justice system is the longest and most impressive we have seen in twenty-seven years on the bench. In January 2008, while in Puerto Rico’s commonwealth prison system, CandelarioSantana was examined by mental health professionals. Clinical psychologist Zahira Lespier Torres (“Dr. Torres”), Psy.D., performed the evaluation. Dr. Torres performed a Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and a Raven Progressive Matrices exam. She based her evaluation on a structured clinical interview with Candelario-Santana, clinical observations of him, as well as on information contained in his referring report from the correctional institution. Dr. Torres’ report begins with a short description of Candelario-Santana’s legal background. She states that CandelarioSantana indicated he was the chief (“jefe”) of a gang, and that after being implicated in a crime, he moved to Michigan to live, where he stayed for several years until he was finally arrested there. She made the following “relevant clinical remarks” about Candelario-Santana: he had a proper appearance and personal neatness; he stated that he understood the purpose of the evaluation; and seemed to be well-oriented in time, place, and self. His thought process was logical and coherent, pertinent to the questions asked. His work rhythm was normal, and he performed the tasks independently. His linguistic expression was clear and with appropriate language. The interview flowed as anticipated, with Candelario-Santana maintaining eye contact. The results of Dr. Torres’ exams did not indicate any signs of mental retardation. On the Raven test, which measures intellectual capacity using nonverbal exercises, Candelario-Santana obtained a classification of “Average,” compared to his age peer group. On the MMPI-2, which measures personality traits and clinical scales that may affect a person’s functioning, Candelario-Santana exhibited a profile of “valid.” The scales of validity indicated that Candelario-Santana maintained a balance between self-protection and self-exposure, as well as a moderate pretense of looking calm. In her discussion of the results, as well as in her clinical observations, Dr. Torres noted repeatedly that Candelario-Santana appeared to be anxious and reserved during the interview. According to Dr. Torres, Candelario-Santana accepted responsibility for criminal behavior while invoking his right not to elaborate. She drew associations between Candelario-Santana’s secretiveness and his lifestyle and surroundings. In her summary and recommendations, Dr. Torres again noted that CandelarioSantana had “proper average intellectual resources to work and produce.” She indicated that clinically, Candelario-Santana did not suffer from any severe pathology. She observed that Candelario-Santana possessed a neurotic, rigid, distant style, consistent with a person very concentrated on himself. Among the “protective factors” that Candelario-Santana had in his favor, Dr. Torres included three factors: An absence of severe pathology, family support, and “intellectual resources.” Among the dynamic factors, Dr. Torres noted: A tendency to avoid managing his emotions, poor introspection, restrictions on his ability to manage friendships, and location and stable work. Her ultimate recommendation, if Candelario-Santana was considered for parole, was preventive psychological follow-up and an occupational adjustment. She also suggested working on Candelario-Santana’s social/interpersonal relations with friends and acquaintances. While incarcerated in Puerto Rico’s commonwealth prisons, Candelario-Santana went on to earn his GED. In January 2008, he was selected as the “Student of the Month” in the educational program at the Zarzal Correctional Institution, where he was serving prison time. A little more than one year later, after serving only six years of a twelve-year murder sentence, Candelario-Santana was released from prison in February 2009. Six months later, on October 17, 2009, the massacre at La Tómbola occurred. On November 10, 2009, the government filed a criminal complaint against CandelarioSantana for two counts of being a felon in possession of a firearm, in violation of 18 U.S.C. §§ 922(g)(1) and 924(e). (Cr. 'No. 09-mj-816, Docket No. 3.) In support of the complaint, the government attached an affidavit from FBI Special Agent Kristopher Pagano. (Cr. No. 09-mj-816, Docket No. 3-2.) In his affidavit, Agent Pagano describes evidence that Candelario-Santana illegally possessed a firearm on two occasions, October 17 and November 4, 2009. (Cr. No. 09-mj-816, Docket No. 3-2.) A confidential human source described seeing Candelario-Santana in the Juana Matos Housing Project in Cataño, Puerto Rico, on November 4, 2009. (Id.) The source said that he/she saw CandelarioSantana in possession of a firearm with an extended high capacity magazine in plain view. (Id.) On November 10, 2009, U.S. Magistrate Judge Justo Arenas issued an arrest warrant for Candelario-Santana. (Cr. No. 09-mj-816, Docket No. 4.) On December 16, Candelario-Santana appeared before U.S. Magistrate Judge Camille Vélez-Rivé, under custody of federal agents. (Cr. No. 09-427, Docket No. 10.) We take judicial notice of the following facts surrounding Defendant’s capture and arrest one day earlier, on December 15, 2009. See Fed. R.Evid. 201(b) (providing that a court may take judicial notice of facts that “can be accurately and readily determined from sources whose accuracy cannot reasonably be questioned.”). On December 15, 2009, agents of the U.S. Customs and Border Patrol (CBP) apprehended Candelario-Santana as he and four other individuals approached the shores of St. Thomas, U.S. Virgin Islands, in a private boat. Candelario-Santana initially presented a false identification, providing a Florida driver’s license. Federal agents performed biometric tests and determined that the identification was false. Another CBP Agent, Louis Penn, recognized Candelario-Santana as a fugitive sought by authorities in Puerto Rico. Agent Don Severance then placed Candelario-Santana under arrest. Following Candelario-Santana’s arrest, federal and commonwealth law enforcement officers held a press conference describing the events. The news was widely-reported throughout Puerto Rico at the time. One of Puerto Rico’s main television news stations, WAPA TV, produced a television news announcement, available online, which included footage of the press conference held by law enforcement officials. In the video, U.S. Attorney for the District of Puerto Rico, Rosa Emilia Rodríguez-Vélez, is shown describing the arrest and charges against Candelario-Santana, including his status as an armed career criminal. Roberto Escobar, Director of the Immigration and Customs Enforcement (ICE) in Puerto Rico, is also shown discussing the arrest. The circumstances of Defendant’s arrest were also reported by the Associated Press and Puerto Rico’s leading newspapers, including El Nuevo Día and El Vocero. In a 52-count third superseding indictment returned in October 2012, defendants [1] Aexis Candelario-Santana, [2] Carmelo Rondón-Feliciano, and [4] Wilfredo Candelario-Santana are charged as members of a criminal organization “whose members engaged in narcotics distribution and acts of violence, including murder and attempted murder.” (Docket No. 579 at 1-2.) The overt' acts in furtherance of this conspiracy include twenty-one (21) murders and twenty-one (21) attempted murders. (Id.; Docket No. 590 at 3.) Defendants [1] Aexis Candelario-Santana and [5] David Oquendo-Rivas are specifically charged with having committed violent crimes in aid of racketeering activity for nine (9) murders and twenty-one (21) attempted murders. (Id.) Nine of the murders charged in the indictment occurred on October 17, 2009, the day of La Tómbola massacre. (Id. at 6-7.) III. Expert Reports The court heard testimony from the following four experts in this case. Each of the experts was qualified as an expert without objection. A. Dr. Margarida Dr. Maria Margarida, Psy.D., was the first expert to testify, on December 6, 2012. She was called by the Defendant. Dr. Margarida is a full-time Professor in the Neurology section of the University of Puerto Rico School of Medicine. In 1986, she received a Psy.D. degree in clinical psychology from the Massachusetts School of Professional Psychology. She also received a M. Ed. From Harvard University in 1980. In 1986-1987, she was a postdoctoral fellow in neuropsychology at Harvard Medical School. Her current professional activities today are wide-ranging, including teaching, research, consultation, clinical practice, and private practice. Dr. Margarida does not specialize in mental retardation. Dr. Margarida spent a total of twenty-seven hours with Candelario-Santana during seven separate sessions. She performed a battery of tests using several different instruments. Each of those instruments is listed in her report (“Marg. Rep.”). The most important tests were the “EIWA-III,” a version of the Wechsler Adult Intelligence Scale III that has been normed for Puerto Rico, and the Vine-land II Adaptive Behavior Scales (“Vine-land” or “VABS-II” test), which she administered to two relatives of CandelarioSantana. She testified that CandelarioSantana was fully cooperative with the tests and that she found no evidence of malingering. On the EIWA-III comprehensive intelligence test, Candelario-Santana obtained a full score of 75. (Marg. Rep. at 16.) His verbal score was an 80 and his performance score was a 72. Broken down even further, Candelario-Santana’s score was an 84 on verbal comprehension, 79 on perceptual organization, 77 on working memory, and 59 on processing speed. These results are listed in a table at page 16 of Dr. Margarida’s report. Dr. Margarida testified that the EIWAIII was the only comprehensive intelligence test that she performed. Nonetheless, the table of results on page 16 of her report also lists scores scaled for the WAIS III intelligence test. Dr. Margarida explained that even though she did not actually perform the WAIS III, she saw it fit to include scores scaled to that test, because of her belief that the EIWA-III overestimates scores. (Docket No. 697 at 31.) Dr. Margarida also applied the “Flynn effect” to her results, and provided two columns of “Flynn adjusted scores.” (Marg. Rep. at 16.) Dr. Margarida’s report also refers to the “second prong” of adaptive behavior. (Marg. Rep. at 19.) To assess CandelarioSantana’s adaptive behaviors, she relied heavily on two administrations of the Vine-land II Adaptive Behavior Scales, which were administered in a “semi-structured interview format with two of Mr. Candelario-Santana’s sisters, and score[] his performance as he functioned at 17 years, 6 months age.” (Marg. Rep. at 21.) To do this, Dr. Margarida flew to Worcester, Massachusetts, where eleven of Candelario-Santana’s twelve siblings are now living. (Dec. 6. TR at 41-42.) She spoke to Candelario-Santana’s siblings about their memories of Candelario-Santana when he was age seventeen and one-half years old. Dr. Margarida also performed informal adaptive probes of Candelario-Santana, as well as academic probes, including the Woodcock Muñoz III Achievement Test, Spanish Version. (Marg. Rep. at 25-28.) In Dr. Margarida’s words, “the information gathered in the standardized assessment was validated by cross referring the informant’s responses, with data gathered from informal adaptive probes with Alexis, interviews with collateral sources described earlier, and information from standardized achievement testing using the Woodcock Muñoz Spanish Achievement Battery III.” (Id. at 21.) Regarding the third prong of mental retardation, Dr. Margarida again relied heavily on her interviews with CandelarioSantana’s sisters in Massachusetts, including the two administrations of the Vine-land test. (Marg. Rep. at 30.) She also referred to her academic probes of Candelario-Santana, available records, and interviews with Candelario-Santana and his relatives, which she said indicated the onset of mental retardation before the age of eighteen. (Id.) B. Dr. Herrera Dr. Jorge Herrera Pino (“Dr. Herrera”) was the second expert to testify, on December 7. Dr. Herrera was called by the government. Among many other professional roles, Dr. Herrera is the founder and director of the Miami Neurobehavioral Institute, where he oversees a team of eleven licensed neuropsychologists. Recently he managed a five-year contract from the state of Florida, in which he and his team were responsible for evaluating 5,000 individuals for developmental disability diagnoses. Dr. Herrera estimates that seventy to seventy-five percent of those individuals were evaluated for mental retardation specifically. At the beginning of his career, Dr. Herrera was involved in a large-scale effort to rectify incorrect diagnoses of Hispanic children as mentally retarded by the state of Michigan. A large portion of Dr. Herrera’s career has also involved, up to the present day, international consultation with institutions throughout Spain and Latin America. He sees patients one day a week in addition to his extensive teaching, supervision, consulting, and management responsibilities, which he does for hospitals, universities, and private institutions. He is an Associate Professor and a founding member of the college of medicine at Florida International University. His involvement in the field of neuropsychology stretches some “forty plus years.” He has also testified for both the government and defense as an expert in Atkins hearings, including approximately ten times for the defense in habeas proceedings. Dr. Herrera has a Ph.D. in Educational and Clinical Neuropsychology from Wayne State University, a Doctor of Medicine from Universidad de Alcalá, Spain, and was a post-doctoral fellow for two years in pediatric and clinical neuropsychology, also at the Universidad de Alcalá, Spain. Dr. Herrera met with Candelario-Santana for approximately two hours at the Metropolitan Detention Center, where he performed a neuropsychological diagnostic interview. He prepared a report of his analysis, available as Defense Exhibit 13. In his report, Dr. Herrera also analyzed the findings of a 2008 psychological exam done by Dr. Torres (discussed above), and conducted interviews with four individuals who had known Candelario-Santana well for an extended period of time, including in adulthood. Each interview lasted approximately one-and-a-half hours. Dr. Herrera also reviewed the tests performed by Dr. Margarida and Dr. Grodzinski. (Dr. Grodzinski’s background and findings are discussed below.) Dr. Herrera also performed an “additional eclectic battery of neuropsychological instruments” to complement the test results performed by Dr. Grodzinski. As we discuss further below, Dr. Herrera determined with a high degree of confidence that Candelario-Santana was not mentally retarded. C. Dr. Grodzinski Dr. Jaime Grodzinski Schwartz (“Dr. Grodzinski”) was the second government expert to testify, also on December 7. Dr. Grodzinski received a Psy.D. and M. Sc. in clinical psychology, with an emphasis in neuropsychology, from Carlos Albizu University in Miami, ■ Florida. He has also received graduate degrees and licensures in clinical psychology from institutions in Peru and Israel. Presently, Dr. Grodzinski serves as a neuropsychologist examiner for the Veterans Hospital in San Juan, Puerto Rico, and performs clinical and forensic psychological services for several other government entities. Dr. Grodzinski is also an adjunct professor at Carlos Albizu University, and maintains a private practice. Dr. Grodzinski evaluated CandelarioSantana on three separate occasions, November 13, 19, and 21, for a total of ten hours. The evaluation included a clinical interview, an inquiry into Candelario-Santana’s medical and psychological history, and neuropsychological testing. A complete list of the eighteen tests administered by Dr. Grodzinski is available in his report. While “the main source of information was Candelario-Santana himself,” Dr. Grodzinski also gathered information from the following sources: The indictment; Candelario-Santana’ siblings; the report and raw data by Dr. Margarida; the reports of Drs. Torres and Greenspan; Candelario-Santana’s school records, prison records, and vaccinations records; interviews with four individuals who knew Candelario-Santana well; and transcript of phone calls made by CandelarioSantana. Based on all of this information, Dr. Grodzinski concluded that Candelario-Santana was not mentally retarded. Dr. Grodzinski also concluded that CandelarioSantana’s available records and test results were consistent with post-concussion syndrome and his “psychosocial deprivation” that interrupted his formal education at seventh grade. D. Dr. Greenspan Dr. Stephen Greenspan, the final expert, testified on December 21. (Dec. 21 TR.) Dr. Greenspan received a Ph.D. in developmental psychology from the University of Rochester, and was a post-doctoral fellow in mental retardation and developmental disabilities at UCLA. He is currently a Clinical Professor of Psychiatry at the University of Colorado Health Sciences Center, and Emeritus Professor of Educational Psychology at the University of Connecticut. He has a long history of involvement in the mental retardation field, including in the APA and AAIDD. His work has been cited in the relevant manuals of the AAIDD, and he has testified in several court cases involving mental retardation, including several Atkins determinations in federal courts. Dr. Greenspan’s curriculum vitae is available as Defendant’s Exhibit 10. Dr. Greenspan did not directly examine or interview Candelario-Santana. Instead, Dr. Greenspan provided a “Declaration.” In his “Declaration,” Dr. Greenspan describes his involvement in the case: Def. Exh. 10 at 1. Dr. Greenspan says he has performed similar services in other U.S. court cases, also without actually meeting or interviewing the defendants or any witnesses. In his “findings”, Dr. Greenspan states his professional opinion that Dr. Margarida “used appropriate methods and information for assessing” the three prongs of mental retardation, and that she “appears justified in her conclusion that Mr. Candelario-Santana” meets the three prongs. Dr. Greenspan briefly discusses the reasons for this professional opinion, and cautions against adopting any stereotype of mentally-retarded people. He also warns against using isolated competencies or accomplishments as evidence of mental retardation. It is not clear from Dr. Greenspan’s “Declaration” what information he considered about Candelario-Santana aside from Dr. Margarida’s tests. Although Dr. Margarida is a highly qualified neuropsychologist, she does not specialize in developmental disorders such as mental retardation. Therefore, Mr. Ruhnke engaged my services as a recognized authority on mental retardation, and asked me to examine Dr. Maragrida’s [sic] methods and findings, and opine as to whether or not she is on firm ground in her conclusions. On December 18, days before his testimony, Dr. Greenspan produced a “Supplemental Declaration.” (Def. Exh. 10A.) At the hearing and in subsequent briefings, the defense made almost no reference to this “Supplemental Declaration.” We have reviewed the Supplemental Declaration, and found it to be speculative, inconsistent, and unhelpful. The unhelpfulness of Dr. Greenspan’s Supplemental Declaration is consistent with his otherwise limited, biased and unprofessional involvement in this case. The Supplemental Declaration reviews the reports of Drs. Grodzinski and Herrera and adds additional thoughts about their reports. Our determination that Dr. Greenspan is completely lacking in credibility precludes us from giving any weight to the assertions in his Supplemental Declaration. Under Rules of Evidence 702 and 703, this court has a duty to “ensure that any and all scientific testimony or evidence admitted ... is reliable.” Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 589, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993). We enjoy wide latitude in determining how to assess an expert’s reliability, and we are not limited to the specific factors outlined in Daubert or any other case. See Kumho Tire Co., Ltd. v. Carmichael, 526 U.S. 137, 138, 119 S.Ct. 1167, 143 L.Ed.2d 238 (1999); United States v. Shay, 57 F.3d 126, 132 (1st Cir. 1995) (“A district court’s decision to admit or exclude expert testimony is entitled to great deference.”); United States v. Brien, 59 F.3d 274 (1st Cir.1995) (“[Tjrial judges have traditionally been afforded wide discretion to admit or exclude expert evidence.”). We found Dr. Greenspan’s testimony suffered from extreme deficits to the extent that it was fundamentally unreliable. We conclude that it cannot be used as evidence in rendering our decision today. First, Dr. Greenspan’s testimony contained considerable errors that suggest a certain carelessness and slipshod disregard for the seriousness of our present inquiry. For example, Dr. Greenspan’s declaration, which he signed under penalty of perjury, states unequivocally that he reviewed Dr. Margarida’s final report. (Docket No. 600.) Yet he admitted to the court that he was actually not sure whether he had read her final report (dated the same day as his declaration) or an earlier, non-final draft. (Dec. 21 TR at 80.) Also, Dr. Greenspan’s declaration states that he has personal knowledge of its contents— including his laudatory endorsement of Dr. Margarida’s professional qualifications and reputation. In fact, Dr. Greenspan told the court that he had no personal knowledge of Dr. Margarida’s credentials and only knew of her accomplishments through her CV and some casual internet research. (Dec. 21 TR at 84-5.) It is alarming that Dr. Greenspan would make such misstatements to the court, and we can only conclude (at best) that he was careless in crafting his statements under oath to this court. This behavior unto itself is not consistent with the rigorous standards of diligence and honesty this court requires of expert testimony. Second, Dr. Greenspan was combative and evasive throughout his testimony despite being admonished to be more forthcoming with his answers. (Dec. 21 TR at 69, 71, 73, 76, 78, 86, 87, 88, 93, 98, 103, 105, 109, 113, 114, 182, 211.) Dr. Greenspan’s evasiveness continued even when he was answering questions about his own testimony on cross-examination. (Dec. 21 TR at 111-12.) Dr. Greenspan’s testimony before this court contradicted testimony he has given elsewhere on prior occasions and scholarly writings he has published specifically addressing Atkins hearings. (Dec. 21 TR at 120-122.) On a prior occasion, Dr. Greenspan said that those diagnosed with mild mental retardation cannot read. But before this court he said his previous statement was incorrect and that he should have said that the mentally retarded cannot read “well.” (Dec. 21 TR at 89-91.) He referred to this discrepancy as “a little thing.” (Dec. 21 TR at 89.) Dr. Greenspan also testified in another case that the mental “age” of one diagnosed with mild mental retardation would never be higher than between the age equivalent of eight and eleven. (Dec. 21 TR at 90-91.) Before this court he testified that it would be twelve. (Dec. 21 TR at 90-92.) In his declaration, Dr. Greenspan wholesale endorsed Dr. Margarida’s methods and findings. (Docket No. 600.) But in his testimony he found certain aspects of Dr. Margarida’s methods, including her use of the Vineland Adaptive Behavior Scales, “inappropriate.” (Dec. 21 TR at 177.) Finally, Dr. Greenspan seemed unwilling or unable to explain evidence that tended to refute his conclusions and offered little explanation during his testimony as to why he thought the government’s experts’ assessments were incorrect. (Dec. 21 TR at 111, 113.) He did, however, resort to ad hominem attacks on the governments’ experts’ professional qualifications as a replacement for scientific evidence and arguments. (Dec. 21 TR at 184.) Moreover, Dr. Greenspan criticized certain methods employed by the government’s experts, including IQ screening tests, that he himself has used in the past. (Dec. 21 TR at 139.) In the end, Dr. Greenspan delayed the proceedings unnecessarily and attempted to prevent the government from conducting meaningful cross-examination for the benefit of the court. We do not dispute that Dr. Greenspan can qualify as an expert in this field— certainly his academic credentials and the many plaudits he has received from his professional peers mark him as such. But that does not mean that his testimony before this court was reliable. To the contrary, Dr. Greenspan’s testimony before this court failed to meet the high standards of scientific reliability and evidence demanded in his field. See Kumho Tire Co., Ltd., 526 U.S. at 152, 119 S.Ct. 1167 (reliability can be measured by whether the expert has employed in the courtroom “the same level of intellectual rigor that characterizes the practice of an expert in the relevant field”); Milward v. Acuity Specialty Products Group, Inc., 639 F.3d 11, 26 (1st Cir.2011). Dr. Greenspan was evasive and unhelpful in addressing the court’s questions. He gave no explanation to refute contrary opinions or to support his own opinions when challenged. He gave testimony that contradicted his own prior statements and gave no explanation for having changed his mind. Perhaps most fundamental of all, he told the court under oath that he was familiar with Dr. Margarida’s final report, when in fact, he did not know whether he had looked at a preliminary draft or the final version. Whatever Dr. Greenspan’s professional credentials, it is clear he did not bring them to bear on his testimony and reports before this court. We note this mismatch between Dr. Greenspan’s credentials and his performance here as a warning to other courts who may yet hear his testimony in the future. Dr. Greenspan serves as an expert in cases of this sort across the country, and such service demands an impeccable professional reputation. Carelessness and evasiveness have no place in any courtroom, yet Dr. Greenspan has demonstrated those characteristics amply here, and may do so again elsewhere. IV. Analysis In this section, we analyze our findings with respect to each of the three prongs of mental retardation: (1) sub-average intellectual functioning; (2) adaptive behaviors; and (3) onset before the age of 18. Atkins, 536 U.S. at 318, 122 S.Ct. 2242. A. Prong One: Sub-average Intellectual Functioning In Atkins, the Court stated that a “national consensus has developed against” executing persons with a “known IQ” of less than 70. 536 U.S. at 316, 122 S.Ct. 2242. The Court also observed that “an IQ score of between 70 and 75 or lower” is “typically considered the cutoff IQ score for the intellectual function prong of the mental retardation definition.” Id. at 309 n. 5, 122 S.Ct. 2242 (citing 2 Kaplan & Sadock’s Comprehensive Textbook of Psychiatry 2952 (B. Sadock and V. Sadock eds. 7th ed.2000)). This five-point margin between 70 and 75 is due to the standard error of measurement in administering the test. See Hooks, 689 F.3d at 1168 (noting that a “five-point range” applies on either side of the results); see also Atkins, 536 U.S. at 308 n. 3,122 S.Ct. 2242 (noting that mild mental retardation is a condition “typically used to describe people with an IQ level of 50-55 to approximately 70.”) Candelario-Santana was administered a series of tests measuring his cognitive functioning — both by his own expert and by experts acting on behalf of the government. The court was presented with an IQ score from one comprehensive IQ assessment and a variety of other cognitive assessment tests administered over a period of several months, between February and October of 2012. On the full-scale IQ test Candelario-Santana scored a 75, which exceeds the range typically considered to be mentally retarded. On some sections of the comprehensive IQ test, however, Candelario-Santana scored significantly below a 75, which could be indicative of mental retardation. The testimony of Drs. Herrera and Grodzinski, however, convinces us that this is not the case. 1. Candelario-Santana’s IQ Score Dr. Margarida, an expert for the defense, administered the “Escala de Inteligencia de Wechsler para Adultos — Tercera Edición” (“EIWA-III”) to CandelarioSantana on March 15, 2012. (Def. Exhibit 2 at 16.) The EIWA — III is recognized as a model tool for intelligence testing among Spanish-speakers. See Nicholas S. Thaler & Sharon Jones-Forrester, IQ Testing and the Hispanic Client in Guide to Psychological Assessment with Hispanics, 88 (Lorraine T. Benuto, ed., 2012). The EIWA-III is a Spanish-language adaptation of the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), and it includes the subtests and constructs that are the foundation of WAIS-III testing. Id. However, unlike the WAIS-III, the EIWA-III was adapted and standardized specifically to Puerto Rico. The third edition was developed in cooperation with the Ponce School of Medicine in Puerto Rico to ensure the language and items were culturally appropriate for Puerto Ricans speaking Spanish. See Brígida Hernandez, Elizabeth Horin & et alia, Psychological Testing and Multicultural Populations in Race, Culture, and Disability: Rehabilitation Science and Practice (Fabricio E. Balcazar, Yolanda Suarez-Balcazar, et alia eds., 2010). The EIWA — III was the current version of the test at the time Dr. Margarida assessed Candelario-Santana. (Dec. 7 TR at 29.) The test administered by Dr. Margarida consisted of a global scale and several subscales or subtests, grouped into two general categories, “verbal” and “performance”. (Dec. 6 TR at 30) After administering the EIWA-III, Dr. Margarida found Candelario-Santana to have a Full Scale IQ of 75. In addition, Dr. Margarida found Candelario-Santana to have a Verbal IQ of 80 and a Performance IQ of 72. (Def. Exh. 3 at 1.) The government experts credited Dr. Margarida’s raw scores and her administration of the EIWA-III test. (Dec. 7 TR at 23-24.) We see no reason to disagree with this expert consensus. Furthermore, since the EIWA-III is itself recognized as a mainstream IQ test devised specifically for Puerto Ricans, we see no reason to doubt its suitability in these circumstances. 2. Criticism of IQ Score by Drs. Herrera and Grodzinski Although we credit Dr. Margarida’s administration of the test and the raw data it generated, we do not necessarily credit all of Dr. Margarida’s interpretations of that data. The government’s experts testified that, contrary to Dr. Margarida’s conclusions, the Flynn effect should not be applied here and that Candelario-Santana’s low score on the processing speed subtest of the EIWA-III was better explained by several traumatic brain injuries he sustained, rather than an overall sub-average intellectual functioning. We agree with the government’s experts on both points. The Flynn Effect is a phenomenon named for James R. Flynn, who discovered that the population’s mean IQ score rises over time, by about a third of a point each year. According to Flynn, if an individual’s test score is measured against a mean of a population sample from prior years, then that individual’s score will be inflated in varying degrees (depending on how long ago the sample was first employed) and will not provide an accurate picture of his IQ. See, e.g., Walton v. Johnson, 440 F.3d 160, 177 n. 22 (4th Cir.2006) (en banc) (“The premise of the ‘Flynn Effect’ is that IQ scores increase over time and that IQ tests that are not renormed to take into account rising IQ levels will overstate a testtaker’s IQ score.”); James. R. Flynn, Tethering the Elephant: Capital Cases, IQ, and the Flynn Effect, 12 Psychol. Pub. Pol’y & L. 170, 172 (2006) (“Naturally, judges want to know whether defendants were actually two standard deviations below their peers at the time they were tested and not how they rank against a group selected at some random date in the past.” (emphasis added)). See generally James R. Flynn, The Mean IQ of Americans: Massive Gains 1932 to 1978, 95 Psychol. Bull. 29 (1984). Flynn posited that a downward adjustment to scores is necessary when a test without current norms is used. See Flynn, Tethering the Elephant, supra, at 174-75. However, the Flynn Effect remains highly controversial and many courts have declined to accept its application. See Thomas v. Allen, 607 F.3d 749, 757 (11th Cir.2010) (“[T]he Flynn Effect is a statistically-proven phenomenon, although no medical association recognizes its validity.”); Maldonado v. Thaler, 625 F.3d 229 (5th Cir.2010) (“Neither this court nor the [Texas Criminal Court of Appeals] has recognized the Flynn Effect as scientifically valid.”); Williams v. Mitchell, 2012 WL 4505774, *34-36 (N.D.Ohio 2012) (holding that a state court’s failure to adjust an IQ score to take in account the Flynn Effect was not contrary to clearly established federal law for purposes of 28 U.S.C. § 2254(d)(1); “[C]ourts have held that ‘there is no scientific consensus’ on the validity of the Flynn Effect.”); see also Leigh D. Hagan, Eric Y Drogin and Thomas J. Guilmette, IQ Scores Should Not Be Adjusted for the Flynn Effect in Capital Punishment Cases, Journal of Psychoeducational Assessment (2010); George C. Denkoski and Kathryn M. Denkowski, WAIS-III IQs of Criminal Defendants with Mental Retardation Claims Should Not Be Reduced for the ‘Flynn Effect’, American Journal of Forensic Psychology (2007); Alan S. Kaufman, In What Way Are Apples and Oranges Alike? A Critique of Flynn’s Interpretation of the Flynn Effect, Journal of Psychoeducational Assessment (2010); Michael Shayer and Denise Ginsburg, Thirty Years On-A Large Anti-Flynn Effect?, British Journal of Educational Psychology (2009); As the government’s experts demonstrated, the EIWA-III test administered to Candelario-Santana was not an old test in need of being “renormed.” Recently revised in 2008, the EIWA-III was (and is) a test for contemporary Puerto Ricans and scaled specifically to that population. (Dec. 7 Tr. at 26-31.) Furthermore, the government’s experts could not point to a single instance in their professional experience where they applied, or could recall a colleague’s application of, the Flynn Effect. (Dec. 7 TR at 31.) Moreover, defense’s own experts differed about how to apply the Flynn Effect properly and how many points a proper Flynn Effect adjustment would give to Candelario’s IQ score. (Dec. 21 TR at 87.) Under such circumstances, the Flynn Effect has no relevance to our inquiry and we agree with the government’s experts that it should not apply here. See Hooks, 689 F.3d at 1170 (concluding that neither Atkins nor any other U.S. Supreme Court decision mandates the application of the controversial Flynn Effect). In her report, Dr. Margarida included a scoring sheet that listed Candelario-Santana’s raw and scaled scores from each of the eleven subtests that comprise the EIWA-III. (Def. Exh. 2 at 15.) Raw scores are the actual scores achieved on each subtest. See United States v. Smith, 790 F.Supp.2d. 482, 491 (E.D.La.2011). Scaled scores are raw scores converted into a standardized score, the final score on the test for that category. Id. The scaled scores Candelario-Santana achieved on the administration of the EIWA-III subtests are grouped into four general categories: “Verbal Comprehension,” “Perceptual Organization,” “Working Memory,” and “Processing Speed.” The scores Candelario-Santana received in these four categories were remarkably consistent, save for one obviously outlying score measuring Candelario-Santana’s processing speed. (Dec. 7 TR at 34.) Without processing speed, the scaled scores from the three general categories listed in Dr. Margarida’s report are clustered around a median score of 80. Based on the scores Dr. Margarida obtained from her administration of the EIWA-III, Candelario-Santana scored a 59 on processing speed. (Def. Exh. 2 at 15.) That score is significantly lower than his scores for each of the other three categories. Because a single outlying score is uncommon, Drs. Herrera and Grodzinski conducted additional tests on Candelario-Santana to determine if any clinical reasons, including mental retardation, might explain this outlying score. Drs. Herrera and Grodzinski administered a battery of tests — eighteen separate tests, in fact — aimed at further examining Candelario-Santana’s deficient processing speed. (Def. Exh. 11.) In the course of their tests, Drs. Herrera and Grodzinski determined that, in addition to processing speed impairment, Candelario-Santana had poor hand-eye coordination and memory impairment. (Dec. 7 TR at 36-37.) For example, Candelario-Santana scored very poorly on the Grooved Pegboard Test, which is strongly indicative of underlying motor and eye-hand coordination difficulties. (Def. Exh. 13 at 12.) One of the tests administered by Dr. Grodzinski was the Test of Nonverbal Intelligence (“TONI-IV”). The TONI-IV is a general assessment of intelligence and provides evaluative data of non-verbal learning process, abstract reasoning, and problem solving. (Def., Exh. 11 at 6.) The TONI-IV helps evaluate subjects with questionable or limited language ability. (Dec. 7 TR at 55.) Dr. Grodzinski administered the TONI-IV as a tool that could corroborate the hypothesis that Candelario-Santana suffered from impaired motor skills and sub-average processing speed. (Dec. 7 TR at 54.) The test was not administered as a tool for determining a comprehensive measurement of Candelario-Santana’s intelligence. Id. At the hearing, defense counsel raised questions about the manner in which Dr. Grodzinski scored his administration of the TONI-IV. According to the TONI-IV diagnostic manual, testing should stop when a subject incorrectly answers three successive questions. (Dec. 7 TR at 167.) But, when Candelario-Santana incorrectly answered three questions in a row, Dr. Grodzinski had him continue the test. Dr. Grodzinski explained why he did not follow the specific directions of the diagnostic manual in this particular case: he had suspicions that Candelario-Santana was malingering. Malingering is “intentional production of false or grossly exaggerated physical or psychological symptoms, motivated by external incentives such as avoiding work, obtaining financial compensation, evading criminal prosecution, or obtaining drugs.” See American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders: DSM-IV 683 (4th ed.1994). At the hearing, Dr. Grodzinski testified that Candelario-Santana exhibited a “failure attitude” or “frustration attitude” throughout testing, indicating that Candelario-Santana would frequently indicate that a task was too hard for him and that he could not do it. (Dec. 7 TR at 164-65.) But Dr. Grodzinski also found that, with encouragement, Candelario-Santana often could complete the requested tasks, and often complete them quite well. Dr. Grodzinski also noticed fluctuations in Candelario-Santana’s performance on similar tasks, even some that were familiar to him. Where Dr. Grodzinski expected to see a “practice effect” [the influence of prior test-taking, which generally results in higher scores during a second administration] Candelario-Santana would actually produce results much lower than expected the second time around. (Dec. 7 TR at 166.) Candelario-Santana would read a question very slowly, even though it was a question he had read before. Sometimes, he would read new information very quickly. This behavior can be indicative of malingering. See U.S. v. Smith, 790 F.Supp.2d 482, 497 (E.D.La. 2011) (describing typical malingering tactics-saying “I don’t know” or “I can’t” after answering only a few questions). Even if the individual is not malingering, this behavior still indicates to a clinician that extra encouragement and more testing may produce different results — the testing subject might need encouragement in order to succeed, or might benefit from multiple attempts at similar tasks, rather than accepting an initial failing result. We acknowledge that Dr. Grodzinski was exercising his professional judgment in continuing the test despite the diagnostic manuals contrary instructions. Since we are not considering Candelario-Santana’s specific score on the test, we do not need to deal with the question of whether or not that specific score is accurate based on the test’s diagnostic manual and administrative instructions. Rather, for our purposes, we only note that the test was performed as a means of further analyzing the cause of Candelario-Santana’s disproportionately low score on the processing sub-part of the EIWA-III test. Drs. Herrera and Grodzinski also interviewed Defendant and gained additional information allowing them to understand Candelario-Santana’s impairments more fully. Specifically, they learned that Candelario-Santana suffered head trauma of some kind during the course of his amateur boxing career and during a serious motorcycle accident in which CandelarioSantana was not wearing a helmet. Also, there was no history of mental retardation in Candelario-Santana’s family. Based on these facts, set alongside Candelario-Santana’s scores in the other categories of the EIWA-III and the additional testing they performed, Drs. Herrera and Grodzinski concluded that Candelario-Santana likely suffered from a cognitive impairment that limited his ability to “put the motor act into effect.” (Dec. 7 TR at 37.) Or, in other words, an impairment that clinicians might associate with brain trauma, but that in no way limits Candelario-Santana’s “ability to think, to discern, to think rationally, act with purpose.” (Id.) In all of this, we remember that, as noted by Dr. Margarida, evaluating a person’s mental capacities is both an art and a science. (Dec. 6 TR at 96.) While all of the tests administered by the respective experts are valuable assessment tools, they are just that: tools. Dr. Herrera made the same point in his testimony, when he stated: “[TJests don’t make a diagnosis, just as much as x-rays don’t make a diagnosis.” (Dec. 7 TR at 34-5.) A final diagnosis is only “as good as the thinking process of the ... health care professional that has to make the determination.” Id. We have considered the different professional determinations that Drs. Margarida, Herrera, and Grodzinski detailed before this court, recognizing that each professional assessment reflects both the art and the science of psychological evaluation. Given all of the testimony we have heard, we conclude that the best explanation of the data before the court is that Candelario-Santana does not exhibit sub-average intellectual functioning. B. Prong Two: Adaptive Functioning In Atkins, the Court did not provide a firm definition of adaptive behavior limitations. Instead, the Court again referred to clinical definitions, which it said require “significant limitations in adaptive skills such as communication, self-care and self-direction that manifest before age 18.” Id. at 318, 122 S.Ct. 2242. In a footnote, the Court cited the APA and AAMR definitions. Id. at 308 n. 3, 122 S.Ct. 2242. As one district court has observed, the two classifications “essentially measure the same skills.” United States v. Davis, 611 F.Supp.2d 472, 490 (D.Md.2009). In its third footnote in Atkins, the Court described the key features of adaptive behavior limitations as defined by the AAMR and APA. According to the AAMR definition, a person meets prong two if he has “related limitations in two or more of the following adaptive skill areas: communication, self-care, home living, social skills, community use, self-direction, health and safety, functional academics, leisure, and work.” Atkins, 536 U.S. at 308 n. 3, 122 S.Ct. 2242 (citing Mental Retardation: Definition, Classification, and Systems of Supports 5 (9th ed.1992)). The APA definition is “similar”: according to the DSM-IV-TR, a person meets prong two if he has “significant limitations in adaptive functioning in at least two of the following skill areas: communication, self-care, home living, social/interpersonal skills, use of community resources, self-direction, functional academic skills, work, leisure, health, and safety.” Id. (citing DSM-IV 41 (4th ed.2000)). The most recent version of the AAIDD Manual provides a similar definition of adaptive behavior, which is divided into three categories: conceptual, social, and practical. AAIDD, Intellectual Disability-. Definition, Classification, and Systems of Supports (11th ed.2010) (hereinafter the “AAIDD Manual”) at 43. Conceptual skills include receptive and language skills; reading and writing; and money, time, and number concepts. Id. at 44. Social skills include interpersonal skills, social responsibility, self-esteem, gullibility, naiveté, follows rules/obeys laws, avoids being victimized, and social problem solving. Id. The practical category involves activities of daily living (personal care), occupational skills, use of money, safety, health care, travel/transportation, schedules/routines, and use of the telephone. Id. at 44. We find this definition essentially similar to the ones referenced by the Court in Atkins, which we take as our primary reference point and authority. In any case, we have considered both sets of standards — the ones referenced by the Court in Atkins, as well as the more recent definition in the AAIDD Manual — and we find that under either definition, Candelario-Santana has failed to show that he suffers from significant adaptive behavior limitations. Many courts have noted, correctly, that “[ajdaptive behavior is a broader category, and more amorphous, than intellectual functioning.” Davis, 611 F.Supp.2d at 491; see also Smith, 790 F.Supp.2d at 505. Because of the relative subjectivity of the adaptive behavior analysis, the importance of clinical judgment becomes greater under prong two than under prong one. When assessing adaptive behaviors, therefore, courts must make their own independent determinations of the clinicians’ judgment and credibility. See Davis, 611 F.Supp.2d at 491 (noting importance of assessing information that goes to “the relative credibility of the experts” in the case); Smith, 790 F.Supp.2d at 505 (“the Court must rely on its assessment of the relative competence and credibility of the individual experts”). This function has long been performed by district courts when weighing the testimony of dueling experts. Bruce v. Weekly World News, 310 F.3d 25 (1st Cir.2002) (“Accordingly, the district court, qua factfinder, was entitled to make the crucial credibility determination as between the competing expert witnesses.”). In the same vein, we relied here on our own assessment of the experts in this case. Several factors that we discuss below convinced us that Drs. Herrera and Grodzinski exercised better and more informed clinical judgment than Drs. Margarida and Greenspan. Partly, that was because of the more reliable and comprehensive information that went into Dr. Herrera’s analysis. We were also unimpressed by Dr. Margarida’s unsatisfactory explanations for why she ignored much relevant evidence. In Part III.D., above, we discussed our determination that Dr. Greenspan was severely lacking in credibility. Another important factor in our analysis was the relative disparity in each of the psychologists’ backgrounds in mental retardation. In the words of Dr. Greenspan, Dr. Margarida does not specialize in developmental disorders, such as mental retardation. (Def. Exh. 10 at 1.) Comparatively, Dr. Herrera has an extensive background in evaluating children and adults for mental retardation. Indeed, one of the early formative experiences in his career responded to the State of Michigan’s incorrect diagnoses of mental retardation in Hispanic children. Since then, he has led teams that are responsible for evaluating thousands of patients for mental retardation. Dr. Grodzinski also has extensive clinical and forensic experience diagnosing mental retardation for legal purposes in Puerto Rico. Thus, to the extent we had to resolve disputes between the two experts, we were comfortable relying on the long and distinguished experience of Drs. Herrera and Grodzinski. The government has filed a brief, (Docket No. 729), arguing that this court should adopt a list of six factors that the Texas Court of Criminal Appeals uses to evaluate adaptive behavior under prong two of Atkins. See Ex Parte Briseno, 135 S.W.3d 1, 8-9 (Tex.Crim.App.2004). We agree that some of these six factors are logical considerations in evaluating a defendant’s adaptive behavior limitations. For example, the first and third factors ask whether the people who knew him best believed him to be mentally retarded, an