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Evidence Chapter 9 Opinions, Experts, And Scientific Evidence Outline

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Table of Contents
Chapter 9. Opinions, Experts, and Scientific Evidence..............................................................1
A. Lay Opinions..................................................................................................................................1
B. Expert Testimony...........................................................................................................................6

1. Permissible Subjects and Scope......................................................................................................6

2. Reliability......................................................................................................................................10 a. Court-Appointed Experts............................................................................................................................11

*NB: This outline accords with Sklansky, Evidence: Cases, Commentary and Problems 4th ed.

Chapter 9. Opinions, Experts, and
Scientific Evidence
A. Lay Opinions
 Lay witness: a witness who does not testify based on some special expertise.
 Unlike older rules, lay witnesses are free to offer opinions even on ultimate issues.
 To be admissible, opinions expressed by lay witness must be (1) based on witness's own firsthand observations and (2) helpful to the jury.
FRE 701. Opinion Testimony by Lay Witnesses
 If a witness is not testifying as an expert, testimony in the form of an opinion is limited to one that is:
o (a) rationally based on the witness's perception;
o (b) helpful to clearly understanding the witness's testimony or to determining a fact in issue; and

(c) not based on scientific, technical, or other specialized knowledge within the scope of Rule 702.
FRE 704. Opinion on an Ultimate Issue
 (a) In General—Not Automatically Objectionable. An opinion is not objectionable just because it embraces an ultimate issue. 

(b) Exception. In a criminal case, an expert witness must not state an opinion about whether the defendant did or did not have a mental state or condition that constitutes an element of the crime charged or of a defense. Those matters are for the trier of fact alone.

Advisory Committee Note to FRE 701
 Allows opinion and ultimate issue testimony, since witnesses often find difficulty expressing themselves in language which is not an opinion or conclusion. Differentiating between these and "facts" is practically impossible, and a necessity standard for admitting them didn't work.
 If attempts are made to introduce meaningless assertions which amount to little more than choosing up sides, exclusion for lack of helpfulness is called for by the rule.
Advisory Committee Note to FRE 704
 Under FRE 701 and 702, opinions must be helpful to the trier of fact.
FRE 403 provides for exclusion of evidence which wastes time.
o These provisions assure against admission of opinions which would merely tell the jury what result to reach.
o They also exclude opinions phrased in terms of inadequately explored legal criteria.
 E.g.: "Did T have capacity to make a will?" would be excluded, whereas "Did T have sufficient mental capacity to understand the nature and extent of …" would be allowed.
United States v. Meling, 47 F.3d 1546 (9th Cir. 1995)
 D convicted of product tampering after he allegedly tried to poison his wife with bottles of Sudafed laced with cyanide, and covered his tracks by placing five other bottles of laced Sudafed on store shelves, resulting in the deaths of two people.
o After wife collapsed, D called 911 and feigned hysteria to 911 operator and paramedics.
 D challenges TC admitting lay opinion testimony of the 911 operator and the paramedic, both of whom testified that D was feigning grief shortly after the poisonings.
Opinion (Kozinski):
 FRE 701: Lay opinion testimony is admissible if it is rationally based on the perception of the witness and helpful to the jury in acquiring a clear understanding of the issue.
 While treating wife, Paramedic had ample time to form the impression that D was feigning grief.
 911 operator's testimony was rationally based on her perception of D's agitation during emergency call.
o Though a tape of the conversation was played in full, the jury was not in the same position as the 911 operator to compare D's 

behavior with that of other emergency callers or to assess whether it was abnormal.
United States v. LaPierre: witness who has no previous exposure to defendant is no better situated than jury to identify the defendant from a surveillance photograph.
United States v. Jackson: eyewitness identification testimony is helpful to jury even if surveillance photographs are available, since eyewitness had opportunity to compare person in bank surveillance photograph with everyone she had ever met, whereas jury could only compare person in surveillance photographs to the defendant.

Government of the Virgin Islands v. Knight, 989 F.2d 619 (3d Cir.
 D found guilty of voluntary manslaughter after he repeatedly struck V's head with a pistol, and the gun discharged and killed V.
 D challenges TC's exclusion of an eyewitness' and investigating officer's testimony that firing the gun was an accident.
Opinion (Cowen):
 FRE 701's requirement that a lay opinion be rationally based on the witness' perception requires the witness have firsthand knowledge of the factual predicates that form the basis for the opinion.
o TC properly excluded police officer's opinion because he did not observe the assault.
o The eyewitness, by contrast, did have first-hand knowledge of the facts from which his opinion has formed.
 Having met firsthand knowledge requirement of FRE 701(a), eyewitness'
testimony was admissible if it would help the jury resolve a disputed fact.
o If circumstances can be presented with greater clarity by stating an opinion, then that opinion is helpful to the trier of fact.
o Here, eyewitness' testimony that D fired gun accidently would be helpful to jury.
 Eyewitness described the circumstances that led to his opinion. However, it is difficult to articulate all the factors that lead one to conclude it was an accident.
 To find an error harmless, court must be able to say it is highly probable the error did not contribute to the jury's judgment of conviction.
o The jury could infer from circumstances in this case that the shooting was accidental.
 Eyewitness was permitted to describe fully the circumstances that led to his opinion.
 D himself testified it was an accident, and D counsel argued this theory.

Eyewitness testimony may have been seen by jury as more credible than defendant's testimony, but only a modicum of evidence was necessary to prove the accident theory of defense, because the prosecutor didn't contest it.
Robinson v. Bump, 894 F.2d 758 (5th Cir. 1990)
 P appeals judgment denying relief in negligence action.
o D1 was employed by D2. D3 hit D1's truck on the highway, causing
D1 to lose control and hit P's car, killing P.
o Jury found D3's negligence caused the accident but that D1 was not negligent.
 W, driver of the car following D1, testified that D1 was "in total control"
of the truck until it was struck by D3's vehicle.
 P argues W's testimony constituted either a legal conclusion or an opinion on an ultimate issue.
 Court reviews for abuse of discretion.
Opinion (Duhe):
 FRE 701 permits non-expert to testify in the form of an inference providing the inference is rationally based on the perception of the witness and helpful to a clear understanding of the witness' testimony or the determination of a fact in issue.
 Under FRE 704, testimony in the form of an inference is not objectionable because it embraces an ultimate issue to be decided by the trier of fact.
 While doubtful W was reciting anything more than his observations, the testimony was clearly admissible as an inference of a lay witness.
o W had every opportunity to observe the truck's movement, the movement of a truck is rationally connected to the control of its driver, and the testimony was helpful in allowing the jury to assess
D1's negligence.
 No abuse. Affirmed.
United States v. Ayala-Pizzaro, 407 F.3d 25 (1st Cir. 2005)
 D convicted of possession with intent to distribute heroin.
 D argues TC erred in permitting arresting officer to cross the line from being a fact witness to being an expert witness when the officer testified about drug distribution points and how they operate as well as how heroin is normally packaged for distribution.
o At trial, Officer testified about how the arrest went down. When P
began to ask Officer about his experience with drug points, as a lead-in to Officer's testimony that D was arrested at a known drug point, D counsel objected that P had not given notice of expert testimony from Officer under FRCrimP 16(a)(1)(G).

TC overruled objection to testimony regarding drug points, and held he needed to hear foundational evidence on packaging so allowed it subject to a motion to strike.
o P testified how drug points work: "basically one individual sells while one collects money and others wait around as armed guards and some are lookouts." P testified about his experience with the location of arrest as a drug point.
o P testified that heroin was typically packaged in aluminum decks,
and when asked about drugs seized from D, claimed it was packaged "in a shape or manner of a deck"
Opinion (Lynch):
 Neither type of testimony was expert testimony; both were admissible under FRE 701.
o FRE 701 was amended in 2000 to include requirement that testimony admitted under it not be based on scientific, technical, or other specialized knowledge within the scope of FRE 702.
 The line between expert testimony under FRE 702 and opinion testimony under FRE 701 is not easy to draw.
o The same witness may be qualified to provide both lay and expert testimony in a single case.
 This testimony did not cross the line to become expert testimony.
o Testimony was based on requisite personal knowledge under FRE
602, and also met requirements of FRE 701, because it was based on particularized knowledge the witness had by virtue of his position as a police officer assigned to patrol the neighborhood.
 Testimony did not trigger heightened reliability requirements of FRE

702. o It required no special expertise, defense was not surprised, D had the opportunity to cross-examine, and agent's testimony regarding heroin was not expert testimony.
United States v. Freeman, 730 F.3d 590 (6th Cir. 2013)
 D convicted for murder-for-hire conspiracy.
o D's co-defendant hired D to kill target who had robbed codefendant.
 Main evidence was a series of recorded phone calls. FBI agent testified about his personal impressions of conversations, ranging from voice and nickname identifications to substantive interpretations of meaning of various statements.
o D objected that this testimony was outside scope of notice regarding expertise and the witness' actual expertise. Agent had been qualified as expert on code words and drug slang. Both parties acknowledged the testimony had moved outside the scope of expert qualification.

P responded the testimony was not expert testimony, but was based on agent's personal knowledge. TC overruled objection and allowed agent to testify as lay witness under FRE 701.
o Example:
 Phone conversation: "This shit should be any day now though fam for real. So I'm on it for sure 'cause I need that."
 Agent: "I believe he is referring to the fact that he needs the payments he expects from Co-D if he is successful in locating the target for the purpose of recovering the stolen goods and killing him."
Opinion (Cole):
 P did not establish a proper foundation for the agent's testimony under
FRE 701.
o There is a risk when agent provides interpretations of recorded conversations that he is testifying based on information not before the jury, including hearsay, or at the least that the jury could think he has knowledge beyond that is before them.
 Throughout testimony, agent repeatedly substantiated his responses and inferences with generic information and references to the investigation as a whole (e.g., "we learned over our wiretaps…"
o Jury was left to trust that agent had some information unknown to them that made him better situated to interpret the words used in the calls than they were.
 Agent failed to explain the basis of his interpretations—what experience he had that the jurors themselves did not—and therefore failed to lay a foundation under FRE 701.
 Agent's testimony consisted of opinions and conclusions the jury was well-equipped to draw on their own.
o It was not for agent to divine what vague, plain English means.
These types of conclusions are the province of the jury.
o Distinguishes United States v. Rollins: Agent testified based on thousands of calls that coconspirators had devised a code as they went along, using replacing words to form otherwise nonsensical sentences.
 There, phone calls included cryptic language and the testifier explained what personal knowledge he used in interpreting it.
 Here, Agent testified not only about code words but also common words used in common ways.
o Jury may have been unduly persuaded by agent's position as an FBI
 An agent qualified as an expert may interpret coded drug language, as Agent did. And a lay witness who has personal knowledge of a particular drug or crime conspiracy may

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