Presentation of evidence - Lay opinions

Learning Outcomes

This article explains presentation of evidence rules on lay opinions, including:

• determining when lay opinion testimony is admissible and when it must be excluded under the Federal Rules of Evidence;
• articulating and applying the three FRE 701 requirements—rational basis in perception, helpfulness, and absence of specialized knowledge—in bar-exam style fact patterns;
• distinguishing proper lay opinions from expert testimony governed by FRE 702 and from inadmissible legal conclusions that invade the province of the factfinder;
• recognizing classic admissible topics such as speed, distance, appearance, intoxication, emotional state, identity, and value of one’s own property, and contrasting them with medical or technical opinions that require experts;
• evaluating whether a witness has sufficient personal knowledge and familiarity to give opinions on identity, handwriting, or voice;
• spotting common MBE traps involving police officers, business owners, and other quasi‑experts who offer specialized conclusions while labeled as lay witnesses;
• choosing and justifying the best evidentiary objection to improper lay opinion testimony on multiple‑choice questions;
• converting improper lay opinion statements into admissible factual testimony or narrowly tailored opinions that satisfy FRE 701;
• using a structured, three‑step checklist to quickly analyze lay opinion issues under exam time pressure.

MBE Syllabus

For the MBE, you are required to understand the rules governing opinion testimony by lay witnesses and how they differ from expert opinions, with a focus on the following syllabus points:

• The general rule favoring factual testimony and the exceptions allowing lay opinions.
• The three requirements for admissible lay opinion testimony (FRE 701).
• The distinction between lay and expert opinion evidence (FRE 701 vs. FRE 702).
• Typical situations where lay opinions are permitted and where they are not.
• Limits on lay opinion subject matter, including medical, technical, and legal conclusions.

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

1. Which of the following is NOT a requirement for admissible lay opinion testimony?
   1. The opinion is rationally based on the witness’s perception.
   2. The opinion is helpful to understanding the testimony or a fact in issue.
   3. The opinion is based on scientific, technical, or specialized knowledge.
   4. The opinion is not based on specialized knowledge.
2. A witness testifies that a driver "looked drunk" after a car accident. Is this testimony generally admissible?
   1. Yes, if the witness observed the driver’s behavior.
   2. No, because only experts can give opinions on intoxication.
   3. Yes, but only if the witness is a police officer.
   4. No, because lay opinions are never admissible.
3. In which situation is a lay opinion most likely to be inadmissible?
   1. Estimating the speed of a vehicle.
   2. Stating that someone appeared angry.
   3. Giving a medical diagnosis.
   4. Describing a person’s apparent age.

Introduction

Lay opinions are a frequent topic on the MBE. The general rule is that witnesses testify to facts, not opinions. However, courts allow lay witnesses to give opinions in limited, carefully controlled circumstances. Knowing when a lay opinion is admissible—and when it crosses the line into expert territory or impermissible legal conclusion—is essential for answering MBE questions correctly.

Key Term: Lay Witness
A non‑expert witness who testifies based on firsthand observations and personal knowledge, rather than on specialized, scientific, or technical training.

Key Term: Lay Opinion
Testimony by a lay witness expressing an inference or conclusion based on the witness’s own perception, rather than specialized knowledge.

Lay opinion questions often hide in fact patterns that look straightforward: a driver “seemed drunk,” a man “looked about 60,” or a witness “acted like a madman.” The exam may ask whether such testimony is admissible, or may test whether the correct objection is that the opinion is speculative, based on specialized knowledge, or a legal conclusion.

General Rule: No Opinions

The default rule is that witnesses must testify to facts they observed, not their opinions or conclusions. This allows the jury or judge to draw its own inferences from the facts.

For example, a witness ordinarily states, “The light was red and the car did not stop,” rather than, “The driver was negligent.” The first is factual; the second is a legal conclusion.

Key Term: Personal Knowledge
A witness’s knowledge gained through direct perception—what the witness actually saw, heard, or otherwise sensed—rather than speculation or secondhand information.

Under FRE 602, all witnesses (including lay witnesses) must testify based on personal knowledge. The lay opinion rules build on this requirement.

The preference for fact testimony reflects several policies:

• It prevents witnesses from usurping the factfinder’s role of drawing inferences.
• It avoids unfair weight being given to a witness’s label or conclusion (e.g., “negligent,” “fraudulent”).
• It reduces the risk that the jury will be confused by conclusory or vague terms that hide the supporting facts.

However, strict adherence to “facts only” can sometimes make testimony cumbersome or less clear. In those situations, narrowly tailored lay opinions are allowed.

Exception: Admissible Lay Opinions (FRE 701)

Courts allow lay opinions when strict factual description would be difficult, cumbersome, or less helpful to the factfinder. The Federal Rules of Evidence (FRE 701) permit lay opinion testimony if three requirements are met:

1. The opinion is rationally based on the witness’s perception.
2. The opinion is helpful to understanding the witness’s testimony or determining a fact in issue.
3. The opinion is not based on scientific, technical, or other specialized knowledge (which would trigger the expert rules of FRE 702).

Key Term: Rationally Based on Perception
The opinion must arise from what the witness personally saw, heard, or otherwise sensed, and the inference must be a reasonable one drawn from those observations.

This requirement essentially ties lay opinions back to Rule 602. A lay witness cannot speculate or guess; there must be a concrete observational basis. The “rationally based” test is not demanding, but it does exclude wild speculation (e.g., a stranger testifying that someone “must have been lying about their income” without any basis).

Key Term: Helpful to Trier of Fact
The opinion must clarify the witness’s testimony or make a fact in issue easier to understand; it should add clarity, not confusion or needless detail.

The “helpful” requirement is often satisfied when an opinion is a convenient shorthand for complex sensory impressions. For example, describing someone as “drunk” may convey more effectively the witness’s impressions of slurred speech, unsteady gait, and odor of alcohol. However, if the opinion adds nothing beyond what the jury can already infer from the facts, the court may exclude it as unhelpful or cumulative.

Key Term: Trier of Fact
The decision‑maker in a case—either the jury in a jury trial or the judge in a bench trial.

Key Term: Not Based on Specialized Knowledge
The opinion must not rely on scientific, technical, or other expert‑level knowledge or training; it must be something an ordinary person could infer from everyday experience.

Key Term: Specialized Knowledge
Knowledge or professional skill derived from scientific study, technical training, or professional experience that goes beyond what an average layperson knows.

This third requirement is especially important on the MBE. In 2000, FRE 701 was amended to ensure that parties could not evade the expert‑witness rules by calling experts “lay witnesses” and offering specialized opinions through them. Any opinion that depends on specialized methods, training, or experience belongs under FRE 702 and requires proper qualification.

On the MBE, when a lay opinion is challenged, check each of these elements systematically. If any one fails, the lay opinion is inadmissible.

Key Term: Factual Basis
The preliminary facts that must be shown—such as opportunity to observe and basis of knowledge—before a particular item of evidence or type of testimony is admitted.

Preliminary Requirements and Procedure

Before a lay opinion is admitted, a preliminary showing must establish:

• The witness had a meaningful opportunity to observe the person, object, or event.
• The opinion logically flows from those observations.
• The opinion will assist, rather than distract, the trier of fact.

This is essentially about establishing a sufficient factual basis. The proponent must show that the opinion comes from actual observations and that those observations support the conclusion.

Courts have discretion to require the witness to describe the basic facts first, and then state the opinion. For example, a witness might first testify that a driver was swerving, slurring speech, and smelled of alcohol, and only then say the driver “seemed drunk.”

This sequencing serves two purposes:

• It helps the judge decide whether the opinion is rational and helpful.
• It lets the jury evaluate how much weight to give the opinion, knowing the supporting observations.

Some jurisdictions (not the Federal Rules) are stricter and allow lay opinions only where it is practically necessary—that is, where the perception is difficult to convey without using an opinion word (e.g., “drunk” instead of a long list of observed behaviors). For the MBE, apply the FRE “helpfulness” standard, not a strict “necessity” test.

Procedurally, opposing counsel must object to improper lay opinion testimony or the objection is usually waived. Typical objections include:

• The opinion lacks a factual basis (no showing of perception or familiarity).
• The opinion calls for a legal conclusion.
• The opinion is based on specialized knowledge without expert qualification.
• The opinion is speculative, not rationally based on perception.

If the objection is sustained, the witness may often still testify to the supporting facts, just not to the conclusory label.

Common Subjects for Lay Opinions

Lay opinions are commonly allowed where everyday experience is enough to support a reasonable inference. Typical examples include:

General appearance or physical condition

• “He looked tired,” “She appeared ill,” “He seemed elderly,” or “She looked strong.”
• A witness may estimate height, weight, or age (“about six feet tall,” “around 40 years old”).

However, “He had a fractured skull,” “She had a concussion,” or “He suffered a heart attack” usually crosses into medical diagnosis and requires expert testimony.

Courts allow general statements about someone “looking sick” or “weak,” but they typically exclude specific diagnoses or complex assessments such as “permanent disability” unless an expert is testifying.

Emotional states

• “He looked angry,” “She seemed frightened,” “They appeared to be joking,” or “They seemed affectionate and in love.”
• These are ordinary inferences from facial expressions, tone of voice, and conduct.

These opinions often help the jury understand the context of words or actions—e.g., whether a statement was made in jest, in fear, or in rage. On the MBE, such emotional impressions are generally admissible so long as there is some observational basis.

Matters involving sense recognition

• Descriptions such as “The object was heavy,” “The package was bulky,” “The liquid smelled like gasoline,” or “It tasted like whiskey.”
• These rely on everyday sensory experiences.

A witness may compare smells, sounds, or tastes to familiar items (“It sounded like a gunshot”). The key is that these are ordinary comparisons, not technical identifications (e.g., “That was definitely a gunshot from a 9mm handgun fired from 50 yards away,” which sounds expert‑like).

Speed of moving objects

• A witness who regularly observes vehicles may estimate speed (“about 60 miles per hour”) or use qualitative terms (“very fast,” “crawling along”).
• No expert accident reconstruction is needed for basic speed estimation.

Some courts require a minimal factual basis that the witness has at least some experience observing vehicles at various speeds, but this is usually easy to satisfy. The witness need not be a mechanic or accident reconstructionist.

On the MBE, an answer choice suggesting that speed estimates are inadmissible because the witness is “not an expert” is almost certainly wrong if the witness personally observed the vehicle.

Distance, size, and value (in limited situations)

• Rough estimates of distance (“about 50 feet away”) or size (“about six feet tall,” “roughly three feet wide”).
• A person may also give an opinion about the value of their own property or services, based on familiarity.

Owners are often allowed to give lay opinions about the value of their own land, vehicles, or other property, as well as the value of their own services. This is treated as grounded in personal knowledge and everyday acquaintance with the property or services, not specialized appraisal knowledge. The weight of such testimony can be challenged on cross‑examination.

Identity of a person, handwriting, or voice

A witness familiar with a person, their handwriting, or their voice may offer opinions on identity:

• “That was John’s voice on the phone.”
• “The signature on the contract is Jane’s handwriting.”
• “The person in the security video is my coworker.”

A preliminary factual basis is required to show genuine familiarity.

Key Term: Voice Identification
A lay opinion that a particular voice belongs to a specific person, based on the witness’s familiarity from prior hearing of that person’s voice.

Key Term: Handwriting Identification
A lay opinion that particular handwriting belongs to a specific writer, based on the witness’s prior familiarity with that person’s writing, not acquired for litigation.

In most jurisdictions, familiarity with voice or handwriting must arise from contacts independent of the current litigation (e.g., prior dealings, friendship, business correspondence). Familiarity gained solely for purposes of the lawsuit can be problematic, especially for handwriting; experts are usually used in that situation.

Intoxication

Intoxication is a classic lay opinion subject. A witness who observed a person’s behavior may testify that the person “was drunk” or “did not appear intoxicated,” so long as it is rooted in observed facts (slurred speech, unsteady gait, smell of alcohol, glassy eyes).

In some states, a factual basis must include specific observations (e.g., smell of alcohol, bloodshot eyes) before the opinion “he was drunk” is allowed. Under the Federal Rules, the court has discretion but will often permit the opinion if it is clearly based on a described interaction.

Rational or irrational conduct (sanity‑type observations)

A witness may describe conduct as “rational,” “irrational,” or “she was acting like a madwoman,” based on observed behavior. Some jurisdictions allow a lay opinion that someone was “sane” or “insane,” but many prefer descriptions of behavior plus general impressions of rationality.

These opinions must be drawn from personal observation of how the person spoke, behaved, and responded to events. They do not substitute for expert psychiatric testimony when a complex mental‑health diagnosis is at issue, but they can be part of the overall picture.

These categories are highly testable on the MBE. When a question presents one of these subjects, the lay opinion is usually admissible so long as the three FRE 701 requirements are met and no separate rule (like hearsay or Rule 403) bars it.

Prohibited Lay Opinions

Lay witnesses cannot give opinions that stray into areas requiring specialized knowledge or that amount to pure legal conclusions.

Key Term: Legal Conclusion
A statement that applies a legal standard or label—such as “negligent,” “valid contract,” or “agent”—to facts, effectively resolving a legal issue reserved for the court or jury.

Commonly prohibited lay opinions include:

Medical diagnoses

• “He had a heart attack.”
• “She had a concussion.”
• “The injury caused permanent nerve damage.”

A lay witness may describe symptoms (“He clutched his chest and collapsed,” “Her pupils were unequal”), but may not diagnose a condition. Medical status and causation typically require expert testimony.

One caveat: some very simple medical inferences may be allowed as lay opinions when they are within common understanding (e.g., “His arm was broken” when the bone was protruding). The MBE, however, often expects you to treat specific diagnoses as requiring an expert.

Technical or scientific conclusions

Opinions about engineering defects, ballistics trajectories, complex financial valuations, accident reconstruction, or forensic analysis generally require expert testimony. If the subject matter itself sounds technical or scientific, assume that a lay witness cannot offer a reliable opinion unless qualified as an expert.

Legal conclusions, including agency and contract

Lay witnesses cannot simply attach legal labels to relationships or events:

• Statements such as “He was negligent,” “That was a valid contract,” “She had the intent to kill,” or “He was liable for breach of fiduciary duty” usurp the role of the trier of fact and are usually excluded.
• A witness should not say, “We had a contract.” The proper testimony is a description of the words used and actions taken; the court or jury decides whether those facts amount to a contract.
• A witness may not simply opine, “I was authorized to act for the company.” Instead, the witness must describe employment, title, and instructions; the court or jury decides agency.

These are classic examples on the exam. When you see a witness using legal terms of art—“offer,” “acceptance,” “negligent,” “agent,” “duress,” “involuntary”—look for an answer choice identifying the problem as an improper legal conclusion.

Opinions based on specialized knowledge the witness happens to have

Sometimes a witness has specialized training (e.g., a nurse, engineer, or police officer) but is testifying as a lay witness. That witness may still give ordinary lay opinions based on everyday observations (e.g., estimating speed, describing intoxication). However, they cannot use their specialized background to offer expert‑type conclusions without being qualified under FRE 702.

For example, a police officer:

• May give a lay opinion about how fast a car was going, based on visual observation.
• May not, as a lay witness, testify that the pattern of skid marks shows that the driver was going exactly 72 miles per hour or that the collision was caused by “over‑steering,” which uses accident‑reconstruction techniques.

On the MBE, if the question emphasizes the witness’s specialized training or decades of professional experience and connects that to the opinion, suspect that FRE 701(c) is violated and expert qualification is required.

Distinguishing Lay from Expert Opinion

The line between lay and expert opinion is a major MBE test point. The key is why the witness can offer the opinion:

• If the opinion stems from ordinary experience and everyday reasoning (e.g., estimating speed, recognizing intoxication), it falls under FRE 701 as a lay opinion.
• If the opinion relies on training, professional skill, or specialized methods (e.g., identifying drug packaging practices based on years of narcotics enforcement), it falls under FRE 702 and requires expert qualification.

Key Term: Ultimate Issue
A factual question that the jury or judge must decide in order to resolve the case, such as whether the defendant acted negligently or whether a contract was formed.

Both lay and expert testimony can sometimes touch on ultimate issues, but they must do so in an appropriate way:

• A lay witness may give opinions that bear on the ultimate issue if they are otherwise proper (e.g., “He was driving very fast,” “She appeared angry”), leaving the legal conclusion (e.g., negligence, intent) to the jury.
• Experts under FRE 704 generally may express opinions on ultimate issues in civil cases and most criminal elements, with limited exceptions regarding a criminal defendant’s mental state.

The main problem with lay opinions is not that they touch on ultimate issues, but that they either require specialized knowledge or directly state a legal conclusion.

Examples of borderline scenarios:

• A police officer estimating a car’s speed based on personal observation is giving a lay opinion.
• The same officer testifying that the way drugs are packaged indicates intent to distribute is typically offering an expert opinion based on specialized narcotics experience.
• A business owner testifying that their revenues have “collapsed” after a competitor’s conduct is giving a lay opinion based on personal knowledge of the business.
• The same owner testifying that complex accounting entries prove fraudulent intent would likely be giving an expert‑type opinion requiring specialized accounting knowledge.

On the MBE, if the fact pattern emphasizes specialized training, experience, or methodology, assume the testimony is not a proper lay opinion.

Lay Opinion and Credibility Issues

Lay witnesses sometimes offer opinions that implicitly comment on another witness’s credibility (e.g., “He seemed to be lying,” “She was telling the truth”). Courts are wary of this because credibility is squarely within the jury’s province.

Although the Federal Rules do not explicitly bar all such opinions, most courts exclude them as unhelpful and as invading the role of the factfinder. On the exam, if a lay witness is asked directly whether another witness was “lying,” an objection that the question calls for an improper opinion is likely to be sustained.

Similarly, expert opinions on whether a particular witness is telling the truth are generally inadmissible. The jury assesses credibility.

Worked Example 1.1

A witness testifies, "The car was going very fast, maybe 60 miles per hour." The witness observed the car drive by but is not a mechanic or accident reconstructionist. Is this opinion admissible?

Answer:
Yes. Estimating speed is a classic example of an admissible lay opinion. It is rationally based on personal perception, helpful to understanding how the accident occurred, and does not require specialized knowledge.

Worked Example 1.2

A bystander testifies, "The victim looked like he was having a heart attack." The bystander is not a doctor. Is this opinion admissible?

Answer:
No. This opinion requires medical training and amounts to a diagnosis. The bystander may instead describe what was observed (e.g., “He clutched his chest, turned pale, and collapsed”), but cannot characterize the condition as a “heart attack” without being qualified as a medical expert.

Worked Example 1.3

A friend who has known the defendant for ten years hears a voice on a recorded phone call and testifies, “That is the defendant’s voice.” The friend is not a voice‑analysis expert. Is the testimony admissible?

Answer:
Yes. Voice identification based on familiarity is a proper lay opinion. It is rationally based on the witness’s perception (years of hearing the defendant speak), helpful to determining identity, and does not rely on specialized scientific methods.

Worked Example 1.4

An employee testifies, “I was the company’s agent and had authority to enter into the contract.” The opposing party objects that this is improper opinion testimony by a lay witness. How should the court rule?

Answer:
The objection should be sustained. Whether someone is an “agent” or had “authority” is a legal conclusion. The employee may testify about facts—job title, instructions from supervisors, prior similar transactions—but the existence and scope of agency is for the trier of fact to determine.

Worked Example 1.5

A homeowner testifies, “In my opinion, my car was worth about $8,000 before the collision.” The homeowner is not an appraiser or mechanic. The opposing party objects that the witness is not qualified as an expert. Is the opinion admissible as lay testimony?

Answer:
Yes. Owners may give lay opinions about the value of their own property, based on familiarity and everyday experience. The opinion is rationally based on perception, helpful, and does not require specialized valuation training.

Worked Example 1.6

A witness with EMT training (but not offered as an expert) testifies, “From the way the victim’s leg looked, the bone was definitely broken.” There is no adequate basis for expert qualification. Is this statement admissible as a lay opinion?

Answer:
Likely no as a lay opinion. The statement relies on specialized medical training rather than ordinary experience. Because the conclusion is based on technical knowledge, it falls under expert testimony rules and is inadmissible unless the witness is properly qualified as an expert and the requirements of FRE 702 are met. The witness may instead describe what was seen (e.g., “The leg was bent at an unusual angle”).

Worked Example 1.7

During a breach‑of‑contract trial, a party testifies, “We clearly had a binding contract; we agreed on all the essential terms.” The opposing party objects that the answer is improper opinion testimony. Should the objection be sustained?

Answer:
Yes, at least in part. Whether there was a “binding contract” is a legal conclusion for the court or jury. The witness may testify to the facts—what was said, what was written, what each party did—but should not label the arrangement a “binding contract.” The objection should be sustained as to the conclusory label, though the witness can be asked to describe the relevant conversations and actions.

Worked Example 1.8

In a criminal assault case, a neighbor testifies: “From the way the defendant was shouting and waving his fists, he looked like he wanted to punch the victim.” The defense objects that this testimony states an opinion about the defendant’s intent. How should the court rule?

Answer:
The court should overrule the objection. The witness is describing the defendant’s observable behavior and drawing a common‑sense inference about his apparent intent. This is rationally based on perception and helpful to the jury in understanding the encounter. The testimony does not depend on specialized knowledge and does not use legal terms such as “intent to commit assault”; it is a proper lay opinion.

Worked Example 1.9

A bank’s chief financial officer (CFO) takes the stand as a lay witness and testifies, “Based on my review of hundreds of similar loan files over my career, these particular entries prove that the borrower was engaged in a sophisticated money‑laundering scheme.” The prosecution has not offered the CFO as an expert. Is this proper lay opinion?

Answer:
No. The CFO’s conclusion depends on specialized financial and investigative knowledge developed through professional experience and involves analyzing complex records. Under FRE 701(c), this is expert‑type testimony requiring compliance with FRE 702. As a lay witness, the CFO may describe the entries and the bank’s ordinary practices, but cannot offer this specialized conclusion without being qualified as an expert.

Worked Example 1.10

At a driving‑while‑intoxicated trial, a passerby testifies: “I saw the defendant stumble out of the car, grab the door for support, and speak with slurred words. In my opinion, he was drunk.” The defense objects that this is an impermissible conclusion invading the province of the jury. How should the court rule?

Answer:
The objection should be overruled. The witness has described specific observed behavior and then offered a shorthand opinion—“he was drunk”—based on those observations. Intoxication is a classic subject for lay opinion, and the testimony satisfies FRE 701’s requirements: it is rationally based on perception, helpful to understanding the defendant’s condition, and not dependent on specialized knowledge.

Exam Warning

On the MBE, do not confuse lay opinions with expert opinions:

• If the opinion requires scientific, technical, or specialized knowledge, the witness must be qualified as an expert and FRE 702 applies.
• A lay witness cannot give such opinions, even if the witness actually has specialized training, unless they are formally offered and qualified as an expert.
• Be alert to legal conclusion language—words like “negligent,” “fraudulent,” “valid contract,” or “agent”—which usually signal improper lay opinion.
• Beware of answer choices that state, “Opinion testimony is never admissible from lay witnesses.” That is incorrect under FRE 701.

Another frequent trap is an answer that identifies the wrong problem. For example, the real defect may be that the witness lacked personal knowledge, not that the testimony was an opinion. Always check:

• Did the witness actually perceive the relevant events?
• Is there a rational link between what was perceived and the opinion stated?
• Is the opinion about a permissible lay subject, or is it a disguised expert opinion or legal conclusion?

Revision Tip

When a question involves a witness giving an opinion, use a three‑step checklist:

1. Did the witness personally perceive the relevant events, and is the opinion rationally based on those perceptions?
2. Is the opinion helpful in clarifying testimony or deciding a fact in issue, rather than merely restating the obvious or confusing the jury?
3. Does the opinion avoid relying on specialized or technical knowledge?

If the answer to (3) is “no,” the opinion is not admissible as lay testimony and must meet the expert‑witness requirements instead.

To strengthen recall for the exam:

• Associate lay opinions with everyday impressions: speed, distance, appearance, emotions, intoxication, identity, and value of one’s own property.
• Associate improper lay opinions with legal labels and technical matters: negligence, agency, existence of a contract, complex medical diagnoses, engineering conclusions, and specialized financial or forensic determinations.
• Practice rewriting improper lay opinions into proper factual testimony (e.g., turning “We had a contract” into a description of the parties’ words and actions). This reinforces the difference between facts and legal conclusions.

Key Point Checklist

This article has covered the following key knowledge points:

• The general rule favors factual testimony, but FRE 701 creates a limited exception allowing lay opinions when they are rationally based on perception, helpful, and not based on specialized knowledge.
• Personal knowledge under FRE 602 is a prerequisite for all lay opinion testimony; speculation and guesses without an observational basis are inadmissible.
• Common admissible lay opinions include estimates of speed, distance, and size; general physical condition and age; emotional states; identity of persons, voices, and handwriting based on familiarity; value of one’s own property or services; and intoxication.
• Lay opinions are inadmissible when they require expert or technical knowledge, such as medical diagnoses, scientific or engineering conclusions, complex financial analysis, or specialized law‑enforcement knowledge.
• Lay witnesses may not offer pure legal conclusions on issues such as negligence, the existence of a contract, agency, or the validity of legal rights; they must instead testify to the actual facts.
• The core distinction between lay and expert opinions is whether the inference relies on ordinary experience or specialized training, methods, or professional knowledge.
• A proper factual basis for lay opinion testimony includes showing opportunity to observe, familiarity where required (e.g., voice or handwriting identification), and a logical connection between observations and the opinion.
• On the MBE, many distractor answers misstate the law by asserting that all opinion testimony is inadmissible from lay witnesses or by ignoring Rule 701(c)’s bar on specialized knowledge offered as lay opinion.
• A structured approach—checking perception, helpfulness, and absence of specialized knowledge—helps quickly evaluate the admissibility of lay opinion testimony in exam fact patterns.

Key Terms and Concepts

• Lay Witness
• Lay Opinion
• Personal Knowledge
• Rationally Based on Perception
• Helpful to Trier of Fact
• Trier of Fact
• Not Based on Specialized Knowledge
• Specialized Knowledge
• Legal Conclusion
• Ultimate Issue
• Factual Basis
• Voice Identification
• Handwriting Identification