Objection! How the Federal Rules of Evidence Promote Fair Trials

When two parties clash in a criminal or civil case, one simple word from either lawyer creates instant drama: “Objection!” 

In that moment, a case is thrown into uncertainty. Will a witness statement be struck from the record? Will an expert be permitted to testify? Will a critical exhibit or argument be rejected as legally inadmissible? The answer can make or break a case, and all eyes instinctively turn to the judge.

What’s less clear to the general public is what happens next, and why.

In the federal courts, judges do not resolve such critical questions in a vacuum. Since 1975, they have relied on the Federal Rules of Evidence. These rules provide a consistent but flexible framework to ensure that proceedings remain fair regardless of the court, judge, or type of case.

Before 1975, evidentiary issues were determined by the law of the jurisdiction where the trial took place, and that law was a compilation of cases, rules, and statutes. This posed challenges for lawyers and judges, who had to swiftly address complex or novel evidentiary issues in front of the jury, leading to moments usually reserved for television.

To commemorate the important milestone of 50 years since adoption of the Federal Rules of Evidence, U.S. District Judge Jesse M. Furman, chair of the Rules of Evidence Advisory Committee of the Judicial Conference of the United States, and Professor Daniel J. Capra, reporter for the Advisory Committee, reflect on the impact of unification of the rules of evidence and how the Judiciary’s rule-making process ensures that the Federal Rules of Evidence keep up with the times.

Can you briefly describe what the Federal Rules of Evidence do?

Judge Furman: The Judiciary has authority under the federal Rules Enabling Act to develop rules of practice and procedure for the federal courts. Today, this includes the federal rules governing civil, criminal, and bankruptcy cases, and the rules of evidence that apply in those cases. There are also procedural rules that govern appeals. 

All these rules share the same rule-making process — suggestions to amend one of the five federal rules sets are provided to the relevant advisory committee of the Judicial Conference Committee on the Rules of Practice and Procedure. The advisory committee then considers the suggestion openly and publicly, and if the suggestion has merit, the drafting process takes place. The public is then invited to make comments on the draft amendments and give testimony at public hearings on the proposed changes.

The rules of procedure generally set out the types of filings that are required or can be made in specific types of federal cases, the content of those filings, when a hearing or motion is required, and appropriate deadlines and other mechanisms to move the case forward fairly and efficiently from start to finish. The Federal Rules of Evidence operate differently. They apply only during a specific phase of a case – the trial, and in some limited cases, evidentiary hearings. Their role is to ensure that the facts as determined at trial are based on evidence that is relevant, reliable, authentic, and not unfairly prejudicial. 

For example, a ruling to admit or exclude a piece of evidence that one side may consider “the smoking gun,” or evidence that tests the credibility of a star witness, can be outcome determinative. There are also a host of constitutional issues intertwined with evidentiary decisions, especially in criminal trials, such as Fourth Amendment case law on search and seizure or Sixth Amendment rights to a fair trial and to cross-examine witnesses. 

What prompted the Judiciary to try to codify evidentiary rules for the federal courts and why did it take so long for them to be adopted?

Judge Furman: A major consideration in adopting uniform evidentiary standards was fairness in federal trials. Before 1975, the rules of evidence that applied in a federal trial, including the existence and scope of any privileges from testifying, were scattered throughout federal and state case law and statutes. This disparity raised fundamental concerns about the principle of equal access to justice in the federal court system, a particularly serious concern in criminal prosecutions. 

For example, with differing rules applicable in different federal districts, a witness deemed competent to testify in one federal district might be excluded in another. A unified set of rules was also needed to address the realities of trial practice. Trial judges and practitioners faced the burden of locating the appropriate rule within an extensive maze of case law, often under extreme time pressure with witnesses present and juries waiting. This situation created an obvious need and desire for uniform evidentiary rules in the federal courts. 

Despite consensus that uniform evidentiary rules were needed, the effort to codify the rules of evidence for use in federal trials took almost twenty years, beginning in the late 1950s, when the Judiciary began to study the feasibility of the effort, and ending in 1975, when the rules finally went into effect. This process was at times contentious. For example, many issues were considered issues of law that should not be reduced to formulaic rules, such as privileges recognized as common law or in state statutes.

Looking back on this history, and looking at how the rule-making process works today, it is hard not to appreciate the dedication and commitment shown by the earlier members of the rules committees to see the codification of the evidence rules through to the end.

What is the role of the Advisory Committee on the Rules of Evidence?

Judge Furman: The advisory committee itself has an interesting history unlike the other advisory committees on the rules of procedure. While an Advisory Committee on the Rules of Evidence was established in the 1960s to study and draft the first set of rules of evidence, it was dissolved after they were enacted. The Advisory Committee on the Rules of Evidence was formed again in 1993 and has been evaluating possible amendments to the rules ever since.

Today, our committee is the first line of discussion and consideration of suggestions from the bench, bar, academia, Congress, and the public to amend the Federal Rules of Evidence. We carefully consider these suggestions in public meetings so anyone can see our deliberative process. If the advisory committee finds that a suggestion is appropriate and beneficial to the administration of justice, the reporter to the Committee — Professor Capra — conducts research and drafts a proposed amendment for consideration by the advisory committee. If the advisory committee chooses to proceed, and after giving feedback on the language of the draft, we publish the draft for public comment and a public hearing. Any final amendments yielded by this process are then provided for approval to the Committee on the Rules of Practice and Procedure, the Judicial Conference, and the Supreme Court. Once approved, they become effective unless Congress intervenes.

Our members include trial and appellate judges, trial attorneys, a representative from the Department of Justice, a representative from the federal public defenders’ community, along with liaisons from the other advisory committees. This structure provides invaluable multi-faceted perspectives that ensure rule proposals are examined thoroughly from all relevant angles. 

Evidentiary rules also do not operate in isolation. We have to pay careful attention to how evidentiary rules operate in both civil and criminal cases and how they interact with constitutional requirements. 

What is the role of the Reporter for the Advisory Committee on the Rules of Evidence and what lessons have you learned from that experience? 

Professor Capra: Each committee relies heavily on the services of its official reporter appointed by the Chief Justice. I’ve had the pleasure of serving in that role for 30 years, and I serve alongside the reporters for the other rules committees, all of whom are prominent law professors and leading experts in their respective fields.

My role at the highest level is to bring my expertise in the law of evidence to help the advisory committee evaluate suggestions for amendments, and if appropriate, do the research and drafting necessary to carry a suggestion through to a final rule. In that respect, I serve as the subject matter expert on not only the Federal Rules of Evidence themselves, but the case law interpreting them, and any issues that may arise in their application or interpretation. Each year, we can receive anywhere from several to dozens of suggestions for amendments. Not every difficulty requires changing the Federal Rules of Evidence, though, and I’ve seen circumstances where a good suggestion does not lead to a final rule amendment. 

The most fundamental lesson I have learned and that the advisory committee adheres to is that evidentiary rules should articulate core principles while affording courts the discretion necessary to apply them to varied and evolving factual circumstances. This purposeful flexibility has proven to be the Federal Rules of Evidence's greatest strength in adapting to change. 

Another thing I have learned is that having clear and comprehensive committee notes is very important. Many people say that lawyers do not read the committee notes, but these notes explain the purpose of amendments, address specific interpretive questions, provide examples of proper application, and identify issues that the amendment does not resolve. I’ve researched the issue and learned that committee notes in the Federal Rules of Evidence have been cited about 1,800 times in court decisions. 

What do you consider the most significant accomplishments of the Advisory Committee? 

Professor Capra: Since 1993, when the Advisory Committee was reestablished, the rulemaking process has generated approximately forty amendments to the Federal Rules of Evidence. Each of those amendments were significant in some respect.   

Looking back at my 30 years as Reporter, however, it is hard not to think about changes made to Rule 702 governing expert testimony after the Supreme Court decided Daubert v. Merrell Dow Pharmaceuticals, Inc. The case involved the allegation that the defendant’s drug caused birth defects in the plaintiff child. The issue of whether the drug caused the birth defect was obviously a central issue in the case. 

Both sides introduced expert testimony on the issue, in a classic battle of the experts situation, and the trial court relied on existing Supreme Court precedent in a decision called Frye, and not Rule 702, to decide the admissibility of the expert opinions. The Supreme Court rejected this approach and decided that Rule 702 governing expert opinions – and not Frye - applied across the federal courts. 

This decision solidified the role of the trial judge as the gatekeeper in admitting expert testimony under Rule 702. It also led to amendments to Rule 702 to ensure that judges will not allow experts to testify, even if highly qualified, unless it is shown that they conducted a thorough investigation, relied on the same methodologies that they would rely on in their lives as experts outside the courtroom, and applied that methodology reliably. This was an incredibly important development in the law of evidence, and also in promoting the fairness of trial outcomes, because the credibility of expert testimony often influences the outcome in both criminal and civil cases.  

Another important amendment that comes to mind is Rule 107, which regulates illustrative aids used in every trial, criminal and civil. Examples of illustrative aids could include a computerized reenactment of a shooting to illustrate the party's theory of the case, or a slideshow presentation by a lawyer in closing argument. These aids are not evidence – they are tools that the parties can use to help the jury understand complex evidence or how the evidence together supports a conclusion. Prior to the amendment of Rule 107 in 2024, there was no rule governing the use of aids like this. Instead, the judge would make ad hoc decisions as needed through the authority to control the presentation of witnesses and evidence. 

The creation of Rule 107 was therefore designed to address the inconsistency that resulted from the lack of a clear definition of permissible illustrative aids that could be shown to the jury, how and when they could be used, and the judge’s authority to weigh any prejudice that might arise from their use. 

What technological advances have most impacted the Rules of Evidence?

Professor Capra: The use of technology is an issue that the advisory committee has grappled with for decades. This experience yielded an important guiding principle for the advisory committee’s work: where existing rules can reasonably be adapted to new circumstances, the Advisory Committee should favor interpretation over amendment to preserve stability and continuity. 

For example, the transition from paper-based to electronic filing systems in the 1990s and early 2000s presented the first major technological challenge. Following extensive study, the advisory committee determined that existing rules were sufficiently flexible to accommodate electronic filing without substantial amendments. Similarly, the advent of social media, electronic communications, and digital recording technologies presented novel hearsay challenges. After a thorough review, the advisory committee concluded that existing hearsay exceptions adequately addressed these categories of evidence as well. 

In other cases, however, rules changes were needed. For example, inadvertent disclosure of attorney-client privileged information or attorney work-product during electronic discovery led to the adoption Rule 502 governing waiver of attorney-client privilege and protection of attorney work product.

Most recently, AI-generated and AI-processed evidence present fundamental questions regarding authentication, reliability, and the establishment of proper foundations for admission. The advisory committee is currently evaluating whether the proliferation of machine-generated opinions akin to expert testimony can be admissible without a testifying witness, and whether deepfake evidence is a problem in federal trials that needs to be addressed through a potential rule change. 

The challenge in dealing effectively with the use of AI is compounded by the extraordinary pace of technological development in this field. There is legitimate concern that any rule specifically addressing AI drafted today may be outdated by the time the Advisory Committee completes the standard rulemaking process. 

Learn more about the rulemaking process and the history of Federal Rules of Evidence.