Six chapters carry a case file box: a marked space waiting for a matter from the practice to carry the argument. Everything else in this book is complete. Fill the case file boxes in before this goes to print.
What Demonstrative Evidence Is, and Why It Wins Before Trial Starts
A demonstrative is evidence you make to prove a fact, not evidence you found. A photograph pulled from the scene is real evidence. A video built afterward to show how the incident happened is a demonstrative. The distinction sounds academic until a judge excludes the second one and the case goes to trial with only the first.
Evidence versus proof of evidence
Real evidence is the thing itself: the firearm, the rope, the security footage that happened to be running. A demonstrative is something you build to explain or prove what the real evidence means. It didn't exist until your team made it. Courts examine how the exhibit was made, what it purports to show, and whether its foundation supports that use. Scene photographs also require a foundation.
Where the video actually does its work
Demonstratives can be presented to a claims adjuster reviewing exposure before mediation, opposing counsel evaluating settlement, or a judge deciding a motion. Identify the intended use before production. A change in settlement position cannot be attributed to the video alone without examining the other evidence and negotiations.
The cost of getting it wrong
Exclusion can expose a problem with the exhibit's foundation, methodology, or disclosure. It does not necessarily establish a weakness in the underlying claim. A staged or misleading presentation also creates a credibility issue that counsel should address separately from admissibility.
What this book assumes you already know
This book starts where Photography and Videography for Expert Witnesses ends. That book teaches you to capture evidence: camera settings, lighting, scene documentation, chain of custody at the point of capture. This book assumes you can already do that, and teaches you to build the finished exhibit that carries a case: the legal standard it has to clear, the foundation it needs, and the argument it has to survive.
| This book | Photography and Videography for Expert Witnesses |
|---|---|
| Builds the exhibit that proves a fact | Captures evidence at the scene |
| Standard it must clear: Daubert, Frye, Federal Rule of Evidence 702 | Standard it must clear: authentication under Federal Rule of Evidence 901 |
| Reader's next step: foundation, methodology, courtroom defense | Reader's next step: camera, light, lens, card, chain of custody |
Before You Build a Demonstrative
Illustrative Aid or Substantive Evidence: The Line That Sets Your Standard
Two exhibits can look identical on screen and serve different purposes. One is a diagram a witness uses to explain an opinion already in evidence. The other is offered as independent proof of what happened. The intended use, the exhibit's content, and the applicable rules determine the foundation required.
What makes something illustrative
An illustrative aid supports testimony that's already admissible on its own. The witness could describe the same thing in words. The exhibit just makes the words easier to follow. Because the aid carries no independent weight, most courts don't require it to pass Daubert on its own, though the underlying testimony still has to.
What makes something substantive
Substantive, or independently probative, demonstrative evidence asserts a fact by itself. A simulation that reconstructs a fall, a recreation that shows a firearm discharging without a trigger pull: these don't just help the jury follow testimony, they tell the jury what happened. Because the exhibit itself is doing the proving, it has to clear the same admissibility bar as the opinion it represents.
Why the same video can be argued two different ways
Opposing counsel can challenge an exhibit described as illustrative if its content asserts independent proof. State the intended use and request an appropriate limiting instruction. Neither the introduction nor the requested instruction substitutes for examining what the video actually depicts.
How the label changes your foundation testimony
For an illustrative aid, your foundation testimony connects the exhibit to testimony already in evidence. For substantive evidence, your foundation testimony has to independently establish reliability, meaning methodology, data, and error rate, before the judge lets the jury see it. Know which foundation you're laying before you take the stand, not while you're on it.
| Illustrative aid | Substantive evidence | |
|---|---|---|
| Independent evidentiary weight | None, supports testimony | Stands as proof on its own |
| Admissibility bar | Tied to the underlying testimony | Reliability foundation appropriate to the exhibit and jurisdiction |
| Goes to the jury room | Often excluded from deliberations | Typically admitted as an exhibit |
| Typical example | Marked photograph, courtroom sketch | Physics-based simulation, staged recreation |
Classify the Exhibit Before You Build It
Daubert, Frye, and Federal Rule of Evidence 702: The Gatekeeping Rules You're Building For
Identify the rules governing the proposed use before filming. Federal Rule of Evidence 702 and Daubert address expert testimony in federal court. The foundation for a demonstrative also depends on its content, its intended use, and the jurisdiction.
Federal Rule of Evidence 702, the rule you're actually building to
Federal Rule of Evidence 702 lets a qualified expert testify in the form of an opinion if the testimony will help the jury, rests on sufficient facts or data, is the product of reliable principles and methods, and reflects a reliable application of those principles and methods to the facts of the case. The amendment effective December 2023 made explicit the proponent's burden to show admissibility by a preponderance of the evidence.
The five Daubert factors
Daubert v. Merrell Dow Pharmaceuticals identified considerations for testing reliability: can the method be tested, has it been subjected to peer review and publication, does it have a known or potential error rate, do standards exist that control how the technique is applied, and is the method generally accepted in the relevant field. Evaluate the considerations relevant to the method and identify any unsupported part of the foundation.
Why Kumho Tire matters for your kind of testimony
Kumho Tire Co. v. Carmichael extended Daubert's gatekeeping role beyond laboratory science to technical and experience-based expertise, exactly the kind of knowledge a stunt coordinator, an armorer, or a wildfire behavior analyst brings. You don't get to skip Daubert because your expertise comes from decades on set rather than a research lab. You do get to argue that the five factors apply differently to skill-based methodology than to a controlled experiment, and that argument has to be made explicitly, not assumed.
The states that still use Frye
A minority of states, including California and Illinois, still apply Frye v. United States: general acceptance in the relevant scientific community, without the broader reliability inquiry Daubert requires. A Frye jurisdiction asks a narrower question, but general acceptance can be harder to prove for a novel reconstruction method than reliability is under Daubert. Confirm your jurisdiction's standard before you design the methodology, not after.
General Electric Co. v. Joiner, and why losing at the trial court is hard to undo
General Electric Co. v. Joiner set abuse of discretion as the standard of review for a Daubert ruling. Build the trial court record to explain the method, its application, and its limits. Do not rely on an appeal to supply a foundation missing from that record.
| Factor | What it asks | Where the video answers it |
|---|---|---|
| Testability | Can the method be tested and shown false if wrong | Underlying physics or protocol data |
| Peer review and publication | Has the method been reviewed outside your own office | Published standards, prior court acceptance |
| Error rate | What's the method's known or potential error rate | Methodology section of the report |
| Controlling standards | Do standards govern how the technique is applied | Industry protocol you followed and cited |
| General acceptance | Is the method accepted in the relevant field | Literature, prior rulings, professional consensus |
Confirm the Standard Before You Build
How Demonstratives Get Excluded, and How to Build Around Every Reason
Review potential problems with conditions, methodology, error, prejudice, disclosure, and editing before production. The applicable rules and the proposed use of the exhibit determine which objections require attention.
Condition mismatch
A recreation shot under different lighting, distance, materials, or mechanical conditions requires an explanation of whether those differences affect the proposition being demonstrated. A material mismatch can support exclusion even when other parts of the methodology are sound. Chapter six addresses documenting those conditions before filming.
Undisclosed methodology
A demonstrative built on a method the report never explained can prevent the other side from testing its basis. Review the disclosure requirements as well as the method's reliability. The consequences depend on the applicable rules, orders, and circumstances of the omission.
Missing or overstated error rate
Identify the method's known or potential sources of error. If an error rate has not been measured, say so and explain the resulting limits. Do not claim certainty that the method cannot support.
Prejudice that outweighs probative value
Evaluate the recreation's probative value and any risk of unfair prejudice under Federal Rule of Evidence 403. Identify visual choices that add emotional impact without helping demonstrate the relevant facts.
Late disclosure
Check the applicable disclosure deadline before production. Late disclosure creates a separate procedural issue even when the method is sound. Chapter twelve addresses disclosure timing and the need to review the governing rules and scheduling order.
Editorializing that reads as argument, not evidence
Review music, dramatic pacing, and loaded captions for content that adds argument rather than explains evidence. Chapter ten addresses those editing choices. Explain the evidentiary purpose of each retained element.
This chapter is built to carry a real exclusion: a motion your side won or lost, walked through factor by factor. Add the case here before this book goes to print.
Pre-Flight Exclusion Check
Recreation, Simulation, Animation, Illustration: Choosing the Right Category
Distinguish recreation, simulation, animation, and illustration by what the exhibit depicts and how it will be used. Apply the governing rules to its actual function rather than assuming a label alone selects the burden.
Recreation: staging the real event again
A recreation physically stages conditions related to the event. Identify the proposition it tests or illustrates and document the similarities and differences material to that proposition. Do not imply that staging the event again establishes what actually happened.
Simulation: modeling the event from data
A simulation builds a computer model from data rather than staging the event physically. Assess the input data, the model's validation, its assumptions, and its application to the event. Report known error rates and any uncertainty that has not been quantified.
Animation: depicting an opinion that already exists
An animation depicts an expert's opinion about what happened, without independently asserting that the depiction is itself proof. Properly limited, with the right jury instruction, an animation can clear a lower bar than a recreation or simulation, because the jury is told to weigh the underlying opinion, not the video, as the evidence.
Illustration: an aid to testimony
An illustration is a static or simple diagram that aids testimony without depicting the event happening. A trajectory line drawn over a scene photograph is an illustration. Choose it when a diagram accurately explains the testimony without implying a reconstruction that the evidence cannot support.
| Category | Claims to be | Validation burden | Typical foundation witness |
|---|---|---|---|
| Recreation | The event, physically repeated | Document substantially similar circumstances | The expert who staged it |
| Simulation | The event, modeled from data | Validate the model and describe known or potential error | The expert, plus the model's technical basis |
| Animation | An expert's opinion, depicted | Moderate: tied to the opinion's own reliability | The expert whose opinion it depicts |
| Illustration | An aid to testimony | Establish relevance and fair representation for the proposed use | Any witness with personal knowledge of what it shows |
Choose the Category Before You Write the Report
Substantially Similar Circumstances: Building the Foundation Before You Film
A recreation need not duplicate every detail of the event. Identify differences that could affect the proposition being demonstrated and explain their significance. Substantial similarity is part of the foundation, not a guarantee of admissibility.
What substantially similar actually means
Assess whether differences between the recreation and the event affect the proposition being demonstrated. A weather difference requires analysis of its relevance to the physical conditions, visibility, or other matters at issue rather than an assumption that any mismatch requires exclusion.
The variables that matter most
Distance, lighting, and material condition usually matter. The exact make, model, and wear state of a rope, firearm, or rigging component usually matters. The color of the shirt a stand-in wears usually doesn't. Build a list specific to the physics of this case, not a generic list borrowed from a different discipline.
When you can't match a variable
Sometimes the original component is destroyed, degraded, or unavailable. Evaluate whether a documented equivalent or a supported mathematical adjustment can address the difference. If not, consider a different form of demonstration or forgo it. Disclose the mismatch and explain its effect; disclosure alone does not cure a material difference.
Documenting the match before you roll camera
Build a side-by-side comparison sheet, incident conditions against recreation conditions, before the shoot. Record the basis for each match, substitution, and adjustment. Use the sheet to support foundation testimony without treating it as proof that every material condition matched.
This chapter is built to carry a real recreation, walked through variable by variable: what matched, what couldn't, and how the mismatch was disclosed and survived a challenge. Add the case here before this book goes to print.
Pre-Shoot Similarity Check
The Underlying Data: Ballistics, Photogrammetry, Motion Capture, and Sensor Logs
A demonstrative is only as strong as the data feeding it. Beautiful video built on thin data is still thin data. This chapter inventories the data sources that hold up, and what each one needs to survive cross-examination.
Ballistics data and drop-test protocols
For a firearm drop-fire recreation, document drop height, orientation, surface, number of trials, and results across those trials. A single observed discharge documents that occurrence under the tested conditions; it does not establish a failure rate or reproduce the incident by itself. Explain what the protocol and results support.
Photogrammetry and scene measurement
Photogrammetry converts photographs into measured three-dimensional data. Log the calibration objects, the camera positions, the software, and the basis for the stated measurement uncertainty. Explain limitations in the images, calibration, and reconstruction rather than attributing accuracy to reference points alone.
Motion capture and biomechanical data
Motion capture used to reconstruct a fall, a stunt, or a struggle requires documentation of the stand-in's relevant measurements, including height, weight, and reach. Explain differences from the person involved and whether those differences affect the depicted motion or the resulting opinion.
Sensor logs, event data recorders, and timestamps
Vehicle event data recorders, rigging load cells, and body-worn sensors generate their own chain of custody problem: the data has to be extracted, preserved, and time-synchronized to the footage without alteration. Document the extraction method with the same rigor as the footage itself.
The chain from raw data to rendered frame
Keep a version history for the steps between raw data and finished video: software, settings, manual adjustments, and who made them. Explain any gap in the record and whether it limits verification of the final exhibit.
| Data source | What it needs | How it fails |
|---|---|---|
| Ballistics, drop-test | Documented protocol across multiple trials, stated failure rate | Single trial used to claim a rate or broader reliability without support |
| Photogrammetry | Calibration points, camera log, stated margin of error | Measurements without a stated tolerance |
| Motion capture | Stand-in matched to the real person's measurements | Unmatched biomechanics |
| Sensor, event data | Documented extraction method, time-synchronization | Unexplained gaps between raw data and final cut |
Before the Data Goes Into the Video
Methodology and Error Rate: Writing the Record Daubert Actually Reads
The methodology section should explain the demonstration without requiring a viewer to infer the method from the video. Write the protocol before filming and document any changes made during production.
Write the method before you shoot, not after
A methodology written after the fact, to justify footage that already exists, reads like exactly what it's. Write the protocol first, get it reviewed, then shoot to the protocol. The report should describe what you planned to do and then confirm you did it, not reverse-engineer a plan from what happened to come out of the camera.
Stating a known or potential error rate honestly
If a formal error rate has been established for your method in the literature, cite it. If it hasn't, say so plainly, and explain the steps you took to control for error anyway: repeated trials, independent review, matched conditions. Judges don't expect certainty. They expect honesty about the absence of it.
Peer review and publication, and what to do when your method has none
Peer review doesn't require a journal article. A methodology reviewed by another qualified expert before trial, documented in writing, counts. If no publication exists for a novel method, build the closest available substitute: an independent review, cited industry protocols, or testimony from others who use the same method in their own practice.
Standards controlling the technique's operation
Where an industry standard exists, an ASTM International standard (materials and testing), a Society of Automotive Engineers standard, a National Fire Protection Association code, or a manufacturer protocol, cite the specific standard and explain whether and how you followed it. Where none exists, say that plainly rather than implying one does. Verify each cited edition and explain why it applies to the work and the event under review.
Write This Before You Shoot
Chain of Custody, Metadata, and On-Set Production Discipline
A demonstrative can be scientifically sound and still get kept out because nobody can say, under oath, exactly where the footage has been since the camera stopped rolling. Authenticity is a paperwork problem before it's a legal one.
What metadata a court will ask for
Timestamp, camera and lens identification, location data where available, and file hash values at the point of capture. Strip none of it during editing. If your workflow requires converting formats, preserve the original file untouched alongside the working copy, and be ready to produce both.
Chain of custody from card to courtroom
Log custody and editing access, including who pulled the card, made copies, stored originals, and accessed working files. Explain gaps and their significance rather than assuming a particular duration establishes alteration.
Equipment logs and calibration records
Log the calibration date and method for measuring equipment used in the shoot. Check the applicable calibration interval and any evidence of drift or damage. Explain whether the calibration record supports the measurements used in the exhibit.
The production log that saves your foundation testimony
A same-day production log, who was present, what equipment was used, what conditions were recorded, what takes were kept and why, turns a foundation question on the stand from a memory test into a document review. Build the habit on every shoot, not only the ones you expect to be challenged.
Documentation Trail, Start to Finish
Editing Without Editorializing: Where Persuasion Ends and Prejudice Begins
Review editing choices under Federal Rule of Evidence 403, including their probative value and any risk of unfair prejudice or misleading presentation. Reliability alone does not resolve those questions.
Cuts that inform versus cuts that argue
Check each cut against the purpose of the exhibit and the full record. Removing dead time can change the apparent duration or sequence, so disclose such edits when timing matters. Preserve the raw footage and do not omit material that contradicts the opinion.
Music, slow motion, and color grading: the line
Do not add music solely to produce an emotional response. Distinguish added music from audio that forms part of the evidence. Use slow motion to explain motion that is difficult to observe at normal speed, label the playback change, and retain the normal-speed version. Document color adjustments and avoid changes that distort the conditions shown.
Captions and callouts: labeling fact versus asserting conclusion
A caption reading "fourteen feet" labels a measurement. A caption reading "the dangerous condition" asserts a conclusion that requires its own support. Label measurements and distinguish factual annotations from the opinions they illustrate.
The version you show the judge before the version you show the jury
Prepare a version that accurately explains the evidence and identify the purpose of each element. Address potential unfair prejudice and misleading presentation without assuming a restrained edit guarantees admission.
This chapter is built to carry a real editing decision that got challenged, and the specific cuts, music, or captions that stayed in or came out because of it. Add the case here before this book goes to print.
Before You Lock the Edit
The Expert Declaration and Report: Writing the Words That Defend the Video
The report, declaration, and disclosure should explain the video's method, factual basis, and limits. Those documents support review of the exhibit; their quality does not determine the outcome of a Daubert motion.
Describing methodology so it defends itself
Write the methodology section as if the judge will read it with no other context: what you did, in what order, measured against what standard, with what result. A methodology section that requires the video to make sense has already failed. The words have to stand on their own.
Materials considered, and why the list matters more than it seems to
List every document, photograph, dataset, and prior statement you reviewed before forming the opinion the video depicts. An incomplete list is an invitation for opposing counsel to ask what you left out, and why, in front of the jury.
Anticipating the Daubert challenge before it's filed
Review the report for unsupported assumptions, missing citations, and gaps in the reliability analysis. Address those problems before disclosure, whether or not counsel expects a challenge.
What to attach, and what to reference
Attach the underlying data, the protocol, and the calibration records. Reference, rather than attach, material already in the record elsewhere, and cite it precisely enough that anyone could find it in thirty seconds. A report cluttered with everything is as hard to use as a report missing something.
Report Section Review
Disclosure Timing and Federal Rule of Civil Procedure 26: Don't Let Procedure Kill Good Evidence
A late demonstrative raises a disclosure issue separate from its methodology. Review Federal Rule of Civil Procedure 26, the court's scheduling order, and the rules governing the consequences of late disclosure before setting the production calendar.
The disclosure deadline, and why demonstratives get missed
Federal Rule of Civil Procedure 26(a)(2) requires expert reports, and the exhibits that support them, by the court's scheduling order deadline. Demonstratives get missed because they're often finished last, after the report, as a kind of victory lap. Build the video on the report's timeline, not after it.
Supplementation under Federal Rule of Civil Procedure 26(e)
Review any post-disclosure revision against the original report, the applicable supplementation rule, and the scheduling order. Identify changes to the opinion, methodology, data, or presentation. An unchanged opinion does not by itself establish that a revised exhibit is timely or permissible supplementation.
Rebuttal disclosure timing
A demonstrative built specifically to answer the other side's expert follows the rebuttal deadline, which is typically shorter than the initial disclosure window. Confirm the rebuttal deadline the day the opposing report arrives, not the week the trial date approaches.
State court variations
State court disclosure rules can differ meaningfully from the federal rule, in both deadline length and required content. Confirm the applicable rule for each jurisdiction at the start of the engagement, and don't assume a federal timeline transfers to a state court matter on the same docket.
Calendar Before You Build
Answering the Daubert Motion: Structuring the Rebuttal Affidavit
Identify each ground raised in the Daubert motion and answer it with the relevant record. Do not assume the challenge concerns only one or two methodological details.
Reading the motion for its real target
Identify the specific challenges, such as drop height, error analysis, or dissimilar conditions. Address every ground raised and connect each response to the supporting record.
Structuring the affidavit factor by factor
Organize the rebuttal affidavit so the judge can compare each challenge with its answer and supporting record. Use headings that identify the challenged method, assumption, or application.
When to request a hearing
Request a live Daubert hearing when the dispute turns on something better shown than described: a demonstration of the method itself, live testimony the judge can question directly, or a side-by-side comparison a written brief can't convey. Skip the hearing when the dispute is purely legal, such as which jurisdiction's standard applies, since live testimony adds nothing to a question of law.
What the case law asks the judge to weigh
Address the Rule 702 requirements relevant to the challenge: qualifications, helpfulness, sufficient facts or data, reliable principles and methods, and reliable application. Explain how the record supports the opinion rather than treating methodology as separate from its factual basis.
This chapter is built to carry a real Daubert motion your side answered, structured factor by factor, with the outcome. Add the case here before this book goes to print.
Structuring the Rebuttal
Direct Examination: Laying Foundation for the Video, Live
Prepare foundation testimony that connects the witness's qualifications, the method, and the exhibit to the proposed use. Coordinate the sequence with counsel and the court's rulings.
The foundation questions, in order
Qualify the witness, establish the methodology, connect the methodology to the specific exhibit, and only then move to admit it. Skipping ahead to the exhibit before the methodology is established invites an objection that stops your momentum at the worst possible moment.
Authenticating the recreation live
Before playing the recreation, explain what conditions matched, what could not be matched, and how any differences affect the demonstration. Use the comparison sheet from chapter six to support that explanation.
Introducing the exhibit without over-arguing it
State plainly what the exhibit shows and explain its limits. Coordinate the offer of the exhibit with counsel rather than relying on the video to establish its own significance.
Handling the judge's questions from the bench
Answer the judge's specific question directly. Clarify the factual or methodological basis requested, then return to the examination as directed. A single answer does not resolve other foundation or admissibility issues.
Direct Examination Script Check
Cross-Examination: Defending the Video When Opposing Counsel Attacks the Method
Prepare for challenges to conditions, data, editing, qualifications, and objectivity. Review how each potential challenge bears on the specific opinion and exhibit rather than assuming a fixed order of cross-examination.
The standard attacks, and the order they come in
Prepare answers about the similarity of conditions, the data and its uncertainty, editing choices, qualifications, and objectivity. Counsel can raise those subjects in any order or pursue other weaknesses specific to the exhibit.
Conceding the small point to keep the big one
Acknowledge genuine limitations plainly. Explain whether each limitation changes the result, narrows the opinion, or leaves an unresolved question. Do not assume that a difference is immaterial merely because it appears small.
When to say I don't know
A limitation you didn't anticipate deserves an honest answer, not an improvised one. Say what you know and what you don't. Identify any additional analysis needed before answering further.
Redirect: repairing what cross actually damaged, not everything
Use redirect to address issues raised on cross within the court's limits. Explain any necessary correction or clarification without assuming that revisiting a subject will produce a particular jury reaction.
This chapter is built to carry a real cross-examination on one of your demonstratives, the attacks that came and the answers that held. Add the case here before this book goes to print.
Cross-Examination Preparation
The Settlement Lever: Showing Opposing Counsel the Exposure Before Trial
A demonstrative can support settlement discussions as well as trial presentation. Evaluate its admissibility, its evidentiary limits, and the other side's objections before relying on it in negotiations.
Demonstratives in exposure evaluation
An adjuster evaluating exposure can consider both the exhibit's evidentiary significance and the risk of exclusion. Admission resolves an admissibility dispute, not liability or damages. The effect on valuation depends on what the exhibit establishes and the remaining evidence.
When to show it, and when to hold it
Showing the finished exhibit early, before a mediation or a settlement conference, can move the number without ever going to trial. Holding it can preserve surprise value for trial or for a later, more critical motion. The choice belongs to retaining counsel, but the choice is only real if the exhibit is finished and defensible well before the moment arrives to make it.
Using a demonstrative in mediation
Counsel can use a demonstrative in a mediator's private caucus to explain evidence relevant to exposure. Provide the necessary foundation and limitations so the mediator can present the exhibit accurately.
What happens when the other side has already seen it and settles anyway
A settlement reached after a demonstrative is shared does not establish that the exhibit caused the settlement or would have been admitted at trial. Record what was presented, the objections raised, and any terms that can properly be disclosed.
This chapter is built to carry a real settlement that moved after a demonstrative was shared, with the number before and the number after. Add the case here before this book goes to print.
Deploying the Demonstrative Before Trial
The Ethical Standard That Keeps the Video, and the Witness, Credible
A technically polished video can still misrepresent the evidence. Evaluate the opinion, the data, and the presentation against the applicable legal and professional duties, not personal judgment alone.
The test before you build anything
Test the exhibit against reasonable competing interpretations of the same data. Determine whether any problem lies in the underlying opinion, the selected data, or the presentation, and correct the identified problem before use.
Where advocacy ends and misrepresentation begins
Distinguish supported emphasis from misleading omission. Whether anyone asked about a fact does not determine whether leaving it out is proper. Evaluate whether the omission changes the viewer's understanding of the evidence, the opinion, or its limits.
What happens to your other cases when one video crosses the line
A finding that a demonstrative was misleading can become an issue in a later engagement. Preserve the ruling and its context. Counsel must assess whether and how it can be used in the later proceeding.
Disclosing limitations instead of hiding them
Disclose material limitations and explain their actual effect on the conclusion. Revise or narrow the opinion when the limitation requires it. Do not assume that voluntary disclosure cures the problem or that every limitation leaves the result unchanged.