Evidence Study Guide
Evidence law governs what information is admissible in court proceedings. The course is built around the Federal Rules of Evidence (FRE), which apply in all federal courts and have been adopted (with variations) by most states. Students learn the rules of admissibility — relevance, character evidence, hearsay, privileges, opinions, and authentication — and the policy rationales behind them.
The course begins with relevance (FRE 401-403): evidence is relevant if it has any tendency to make a consequential fact more or less probable, and relevant evidence is admissible unless its probative value is substantially outweighed by the danger of unfair prejudice, confusion, or delay. Character evidence rules (FRE 404-405) restrict the use of a person's character to prove they acted in conformity with that character on a particular occasion, with important exceptions for criminal defendants and victims.
Hearsay is the centerpiece of most evidence courses. An out-of-court statement offered for the truth of the matter asserted is inadmissible unless it falls within an exemption (FRE 801(d)) or an exception (FRE 803, 804, 807). The Confrontation Clause adds a constitutional layer, requiring that testimonial hearsay be subject to cross-examination (Crawford v. Washington). Expert testimony, privileges, authentication, and the best-evidence rule round out the syllabus.
Table of Contents
1Relevance (FRE 401-403)
Relevance is the threshold requirement for admissibility. Under FRE 401, evidence is relevant if it has any tendency to make a fact of consequence more or less probable than it would be without the evidence. This is a very low bar. FRE 402 provides that relevant evidence is generally admissible and irrelevant evidence is not. FRE 403 gives the court discretion to exclude relevant evidence if its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, misleading the jury, undue delay, or needless presentation of cumulative evidence. The 403 balancing test is the most frequently applied evidentiary standard.
Key Doctrines
- Relevance (FRE 401)
- General admissibility of relevant evidence (FRE 402)
- FRE 403 balancing test
- Conditional relevance (FRE 104(b))
- Limited admissibility / limiting instructions (FRE 105)
- Stipulations and their effect on probative value
- Subsequent remedial measures (FRE 407)
- Compromise offers and settlement negotiations (FRE 408)
- Insurance (FRE 411)
Essential Cases
2Character Evidence (FRE 404-405)
Character evidence is generally inadmissible to prove a person acted in conformity with a character trait on a particular occasion (FRE 404(a)). This propensity rule reflects the concern that juries will overweight character evidence. Important exceptions exist: in criminal cases, the defendant may offer evidence of a pertinent character trait, and the prosecution may rebut. FRE 404(b) permits evidence of other crimes, wrongs, or acts for non-character purposes — such as proving motive, opportunity, intent, preparation, plan, knowledge, identity, absence of mistake, or lack of accident (the MIMIC purposes). Habit evidence (FRE 406) is freely admissible because it reflects automatic, semi-reflexive behavior rather than character.
Key Doctrines
- Propensity rule (FRE 404(a))
- Criminal defendant's right to offer character evidence
- Prosecution rebuttal of character evidence
- Other acts evidence (FRE 404(b) / MIMIC)
- Methods of proving character (FRE 405 — reputation, opinion, specific instances)
- Habit evidence (FRE 406)
- Character of victim
- Sexual assault cases (FRE 413-415)
3Hearsay: Rules & Exceptions
Hearsay is an out-of-court statement offered to prove the truth of the matter asserted (FRE 801(c)). It is inadmissible unless it falls within an exemption or exception. FRE 801(d) exempts prior inconsistent statements under oath, prior consistent statements, and prior identifications, as well as admissions by party-opponents. FRE 803 lists exceptions available regardless of declarant availability (present sense impression, excited utterance, state of mind, medical diagnosis, business records, public records). FRE 804 lists exceptions available only when the declarant is unavailable (former testimony, dying declaration, statement against interest, forfeiture by wrongdoing). FRE 807 provides a residual exception for statements with equivalent circumstantial guarantees of trustworthiness.
Key Doctrines
- Hearsay definition (FRE 801(c))
- Non-hearsay purposes (effect on listener, verbal acts, circumstantial evidence of state of mind)
- Prior statements exemption (FRE 801(d)(1))
- Admission by party-opponent (FRE 801(d)(2))
- Present sense impression (FRE 803(1))
- Excited utterance (FRE 803(2))
- State of mind (FRE 803(3))
- Business records (FRE 803(6))
- Public records (FRE 803(8))
- Former testimony (FRE 804(b)(1))
- Dying declaration (FRE 804(b)(2))
- Statement against interest (FRE 804(b)(3))
- Residual exception (FRE 807)
- Confrontation Clause (Crawford)
4Privileges
Privileges protect certain confidential communications from compelled disclosure. Unlike most evidence rules, privileges are not codified in the Federal Rules of Evidence — FRE 501 directs federal courts to develop privilege law through common-law principles. The attorney-client privilege is the oldest and most widely recognized, protecting confidential communications between an attorney and client made for the purpose of seeking or providing legal advice. The psychotherapist-patient privilege was recognized by the Supreme Court in Jaffee v. Redmond. Spousal privileges include the adverse-testimony privilege (one spouse cannot be compelled to testify against the other in criminal cases) and the marital-communications privilege (protecting confidential communications made during marriage).
Key Doctrines
- Attorney-client privilege
- Work-product doctrine
- Psychotherapist-patient privilege (Jaffee v. Redmond)
- Spousal/marital privileges
- Physician-patient privilege
- Clergy-penitent privilege
- Crime-fraud exception
- Waiver of privilege
- FRE 501 (federal common-law approach)
Essential Cases
5Expert Testimony & Daubert
Expert testimony is governed by FRE 702, which allows qualified experts to testify if their specialized knowledge will help the trier of fact. After Daubert v. Merrell Dow Pharmaceuticals replaced the Frye general-acceptance test, federal courts act as gatekeepers, evaluating the reliability of expert testimony using factors such as testability, peer review, error rate, and general acceptance. Kumho Tire v. Carmichael extended the Daubert gatekeeping function to all expert testimony, not just scientific evidence. FRE 703 allows experts to base opinions on facts not in evidence if reasonably relied upon by experts in the field.
Key Doctrines
- FRE 702 (expert testimony)
- Daubert standard (reliability gatekeeping)
- Daubert factors (testability, peer review, error rate, general acceptance)
- Kumho Tire extension to non-scientific experts
- Frye general-acceptance test (still used in some states)
- FRE 703 (basis of expert opinion)
- FRE 704 (opinion on ultimate issue)
- Court-appointed experts (FRE 706)
6Authentication & Best Evidence Rule
Authentication (FRE 901-903) requires the proponent to produce sufficient evidence that the item is what the proponent claims it is. This is a conditional-relevance standard — the court determines whether a reasonable jury could find the item authentic. Self-authenticating documents (FRE 902) include certified public records, newspapers, trade inscriptions, and certified business records. The best-evidence rule (FRE 1001-1008) requires the original document, recording, or photograph to prove its content, unless the original is lost, destroyed, or unobtainable.
Key Doctrines
- Authentication requirement (FRE 901(a))
- Methods of authentication (testimony, comparison, distinctive characteristics)
- Self-authentication (FRE 902)
- Best evidence rule / original document rule (FRE 1002)
- Exceptions to best evidence rule (FRE 1003-1007)
- Chain of custody
- Voice identification
- Ancient documents
Essential Cases
Exam Tips for Evidence
For every piece of evidence on the exam, run through the checklist: (1) Is it relevant under FRE 401? (2) Should it be excluded under FRE 403? (3) Does a specific rule bar it (character, hearsay, privilege)? (4) If barred, does an exception apply? This systematic approach prevents you from missing issues.
Hearsay is almost always tested. First, confirm the statement is offered for the truth of the matter asserted — if offered for another purpose (effect on listener, legally operative words, circumstantial evidence of state of mind), it is not hearsay. Then check exemptions (801(d)), then exceptions (803, 804, 807).
For FRE 404(b), the key is articulating a non-character purpose. Memorize the MIMIC list (Motive, Intent, Mistake/absence of, Identity, Common plan) and always tie the other-act evidence to a specific non-propensity purpose. Then apply FRE 403 balancing.
On Confrontation Clause questions, first determine if the statement is testimonial (made primarily to establish facts for later criminal prosecution). If testimonial, it is inadmissible unless the declarant is unavailable and the defendant had a prior opportunity to cross-examine (Crawford). Non-testimonial statements are governed by the hearsay rules alone.
Privilege questions are tested more than students expect. Always identify the privilege, state its elements, check for waiver (voluntary disclosure to a third party), and check for exceptions (crime-fraud exception for attorney-client privilege).
For expert testimony, apply the Daubert framework: (1) Is the witness qualified as an expert? (2) Is the testimony based on sufficient facts or data? (3) Is the testimony the product of reliable principles and methods? (4) Has the expert reliably applied the methods to the facts? Address each prong separately.
Character evidence rules differ between civil and criminal cases. In civil cases, character evidence is almost never admissible to prove propensity. In criminal cases, the defendant may open the door by offering pertinent character evidence, and the prosecution may then rebut it.
Do not confuse the FRE 403 standard ('substantially outweighed') with a simple balancing test. The rule tilts in favor of admissibility — evidence is excluded only when the prejudicial effect substantially outweighs probative value, not merely when the two are roughly equal.
Frequently Asked Questions
What is hearsay and why is it generally excluded?
Hearsay is an out-of-court statement offered to prove the truth of the matter asserted (FRE 801(c)). It is generally excluded because the declarant was not under oath, the jury cannot observe the declarant's demeanor, and the opposing party had no opportunity to cross-examine. These safeguards — oath, presence, and cross-examination — are considered essential to testing the reliability of testimony. Exceptions exist when circumstances provide equivalent guarantees of trustworthiness.
What is the difference between the Daubert and Frye standards for expert testimony?
The Frye standard (1923) admits expert testimony only if it is based on scientific methods that are generally accepted in the relevant scientific community. The Daubert standard (1993), which replaced Frye in federal courts, is more flexible: the trial judge acts as a gatekeeper and evaluates reliability using factors including testability, peer review, known error rate, and general acceptance. Daubert applies to all expert testimony (per Kumho Tire), not just scientific evidence. Some states still follow Frye.
What is the FRE 403 balancing test?
FRE 403 allows a court to exclude relevant evidence if its probative value is substantially outweighed by a danger of: unfair prejudice, confusing the issues, misleading the jury, undue delay, wasting time, or needlessly presenting cumulative evidence. The 'substantially outweighed' standard tilts in favor of admissibility — the court should exclude only when the dangers clearly and significantly exceed probative value.
When is character evidence admissible?
Character evidence to prove propensity (that a person acted in conformity with their character on a particular occasion) is generally inadmissible under FRE 404(a). Exceptions: (1) a criminal defendant may offer evidence of their own pertinent character trait; (2) a criminal defendant may offer evidence of the victim's character; (3) in homicide cases, the prosecution may offer evidence of the victim's peacefulness. FRE 404(b) separately allows evidence of other acts for non-propensity purposes (motive, intent, identity, etc.). Habit evidence (FRE 406) is always admissible.
What is the Confrontation Clause's impact on hearsay in criminal cases?
The Sixth Amendment's Confrontation Clause guarantees a criminal defendant the right to confront witnesses against them. In Crawford v. Washington (2004), the Supreme Court held that testimonial hearsay is inadmissible against a criminal defendant unless the declarant is unavailable and the defendant had a prior opportunity to cross-examine. Testimonial statements include police interrogation responses, affidavits, and forensic lab reports (Melendez-Diaz). Non-testimonial statements (casual remarks, business records) are governed solely by the hearsay rules.
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