Colorado Rules of Evidence: Hearsay, Shreck Experts, and Privileges

The Colorado Rules of Evidence are the body of rules, adopted by the Colorado Supreme Court, that govern what evidence Colorado state courts admit and exclude in civil, criminal, and contempt proceedings. They are modeled largely on the Federal Rules of Evidence, but they depart from the federal framework in several important places, most visibly in how Colorado handles expert testimony and impeachment by prior conviction. The Court maintains and amends the rules on recommendations from its standing Rules of Evidence Committee, and their stated purpose under Rule 102 is “to secure fairness in administration, elimination of unjustifiable expense and delay, and promotion of growth and development of the law of evidence to the end that the truth may be ascertained and proceedings justly determined.”¹

How the Rules Are Organized

The rules are grouped into eleven articles. Each article covers a distinct piece of evidence law:

Article I (Rules 101–106): general provisions, purpose, scope, and rulings on evidence.
Article II (Rule 201): judicial notice of adjudicative facts.
Article III (Rule 301): presumptions in civil actions.
Article IV (Rules 401–411): relevance and its limits, including character evidence.
Article V (Rules 501–502): privileges, including waiver of attorney-client privilege.
Article VI (Rules 601–615): witness competency, examination, and impeachment.
Article VII (Rules 701–706): lay and expert opinion testimony.
Article VIII (Rules 801–806): hearsay and its exceptions.
Article IX (Rules 901–903): authentication and identification.
Article X (Rules 1001–1008): the best evidence rule for writings, recordings, and photographs.
Article XI (Rule 1101): applicability of the rules.

Where the Rules Apply

Under Rule 1101, the rules govern civil actions, criminal proceedings, and contempt proceedings, except those where the court may act summarily. The privilege rules apply at every stage of every action, without exception.²

Several categories of proceedings sit outside the rules entirely:

Grand jury proceedings.
Preliminary examinations in criminal cases.
Sentencing hearings.
Probation grant or revocation hearings.
Extradition or rendition proceedings.
Issuance of arrest warrants, criminal summonses, and search warrants.
Bail and release proceedings.
Preliminary questions of fact determined by the court under Rule 104.

For special statutory proceedings, the rules apply only to the extent that the specific governing statute does not already address the evidence question.²

Relevance and the 403 Balancing Test

Rules 401 through 403 form the baseline. Rule 401 defines relevant evidence broadly as anything that makes a fact of consequence more or less probable than it would be without the evidence. Rule 402 makes all relevant evidence admissible unless excluded by the U.S. Constitution, the Colorado Constitution, the rules themselves, other Supreme Court rules, or a Colorado statute. Irrelevant evidence is never admissible.¹

Rule 403 is the check. Even relevant evidence may be excluded if its probative value is “substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by considerations of undue delay, waste of time, or needless presentation of cumulative evidence.” Trial judges have considerable discretion under this test, and it shows up throughout Colorado case law any time a party argues that damaging but technically relevant evidence should be kept out.¹

Character Evidence and Prior Bad Acts

Rule 404 generally forbids using evidence of a person’s character or a particular character trait to prove that the person acted in conformity with that character on a particular occasion. The exceptions are targeted.³

A criminal defendant may introduce evidence of a pertinent character trait, and the prosecution may then rebut it. If the defendant introduces evidence of an alleged victim’s aggressiveness or violence, the prosecution may respond with evidence of the same trait in the defendant. In homicide cases, the prosecution may introduce evidence of the victim’s peaceful character to rebut a claim that the victim was the first aggressor.³

Rule 404(b) governs other crimes, wrongs, or acts. Such evidence cannot be used to prove character in order to show conforming conduct, but it can be admitted for other purposes: motive, opportunity, intent, preparation, plan, knowledge, identity, or absence of mistake or accident. In criminal cases, the prosecution must give reasonable advance notice of its intent to introduce this kind of evidence if the defendant requests it.³

Expert Testimony Under the Shreck Standard

Expert testimony is where Colorado diverges most clearly from the federal framework. Colorado courts do not apply Daubert directly. Instead, they follow the test set out by the Colorado Supreme Court in People v. Shreck, 22 P.3d 68 (Colo. 2001).

In Shreck, the Court rejected the older Frye “general acceptance” test as too rigid for modern scientific evidence and overruled prior Colorado decisions that had applied it. The Court held that CRE 702 is the primary standard and that trial courts must act as gatekeepers, making specific findings that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the witness is qualified by knowledge, skill, experience, training, or education; (3) the testimony will be helpful to the jury; and (4) the evidence satisfies the Rule 403 balancing test.⁴

The Court acknowledged the Daubert factors, but said they are neither mandatory nor exclusive in Colorado. The inquiry should be “broad in nature” and consider the “totality of the circumstances” of each case.⁴ In practice, Colorado judges may look at peer review, error rates, and general acceptance as relevant considerations, but no single factor decides the question.

In People v. Martinez, 2024 CO 69, the Colorado Supreme Court clarified that CRE 702 neither requires nor prohibits a formal “offer and acceptance” of an expert by the court. The word “qualified” in the rule refers to the witness’s own credentials, not to a procedural step the court must perform. The absence of a formal tender does not automatically make expert testimony inadmissible, so long as it otherwise satisfies Shreck and CRE 702.⁵

Hearsay and Its Exceptions

The hearsay framework closely tracks the federal model. Rule 801(c) defines hearsay as an out-of-court statement offered to prove the truth of the matter asserted. Rule 802 makes hearsay inadmissible unless an exception applies under the rules, Colorado procedural rules, or state statutes.¹

Statements That Are Not Hearsay

Rule 801(d) carves out two categories of out-of-court statements that are not treated as hearsay at all. Prior statements by a witness — including prior inconsistent statements, prior consistent statements offered to rebut a charge of recent fabrication, and prior identifications — are not hearsay if the witness testifies at the current proceeding and is subject to cross-examination about the statement. Admissions by a party-opponent are likewise not hearsay.¹

Exceptions Regardless of Availability

Rule 803 lists exceptions that apply whether or not the declarant is available. The most commonly invoked include present sense impressions, excited utterances, statements of then-existing mental or physical condition, statements made for medical diagnosis or treatment, recorded recollections, business records, and public records and reports. In criminal cases, the public records exception excludes matters observed by law enforcement officers. Other 803 exceptions cover vital statistics, religious records, family records, ancient documents (at least 20 years old), learned treatises, and judgments of previous convictions.¹

Exceptions Requiring Unavailability

Rule 804 provides additional exceptions available only when the declarant is unavailable. A declarant counts as unavailable if excused by privilege, refusing to testify despite a court order, unable to remember the statement, dead or too ill to appear, or not locatable through reasonable efforts. The key exceptions are former testimony (from a prior proceeding where the opposing party had a chance to cross-examine), statements against interest, and statements of personal or family history. One Colorado-specific gap is worth flagging: Rule 804(b)(2), which corresponds to the federal dying declarations exception, is listed as having no Colorado rule codified.¹

Privileges

Colorado takes a two-track approach. CRE 501 sets out the general rule, but the detailed list of privileges lives primarily in C.R.S. § 13-90-107 rather than in the rules themselves. The statute establishes a broad set of protected relationships in which a person may not be compelled to testify.⁶

The recognized privileges include:

Marital and civil union privilege. Spouses and civil union partners cannot be examined for or against each other without consent, or about confidential communications made during the relationship. Exceptions apply for actions between the parties, crimes committed by one against the other, and serious felonies (class 1, 2, or 3 felonies and level 1 or 2 drug felonies).
Attorney-client privilege. Extends to attorneys and their legal assistants, paralegals, secretaries, and clerks; communications and advice are protected absent the client’s consent.
Physician-patient privilege. Physicians, surgeons, and registered nurses cannot be examined about information acquired in treating a patient, with exceptions when the provider is being sued by the patient.
Clergy privilege. Confidential communications made to priests, rabbis, or ministers in their professional capacity are protected.
Psychotherapist and mental health privilege. Covers licensed psychologists, counselors, social workers, addiction counselors, and their staff, including in group therapy.
Other privileges. The statute also recognizes privileges for certified public accountants; public officers (for communications made in official confidence); victim’s advocates in domestic violence and sexual assault cases; confidential communications from a minor child to a parent in the presence of certain professionals; and peer support team members for law enforcement, firefighters, and emergency medical personnel.

CRE 502, adopted by the Colorado Supreme Court in 2016, addresses inadvertent waiver of attorney-client privilege and work-product protection. An inadvertent disclosure does not waive the privilege if the holder took reasonable steps to prevent disclosure and promptly acted to correct the error. An intentional waiver extends to undisclosed communications on the same subject only if fairness requires it. Disclosures made in federal or other state proceedings do not waive the privilege in Colorado if the disclosure would not have been a waiver under CRE 502 or under the law of the jurisdiction where it occurred.⁷

Witnesses and Impeachment by Prior Conviction

Article VI covers competency, examination, and impeachment. CRE 611 gives trial judges broad authority over the mode and order of proof, and CRE 607 allows any party, including the one that called the witness, to attack the witness’s credibility.

Impeachment by prior conviction is handled differently in Colorado than under the Federal Rules. CRE 609 is reserved, and the subject is governed by C.R.S. § 13-90-101. Under that statute, any felony conviction may be used to impeach a witness’s credibility, and the witness can be compelled to acknowledge the conviction on the stand. In civil cases, felony convictions more than five years old are inadmissible for impeachment. No corresponding time limit exists in criminal cases, and Colorado courts have upheld that distinction against equal protection challenges.⁸

Several other features of § 13-90-101 shape practice. Misdemeanor convictions are not admissible for impeachment, though testimony about a witness’s motive, bias, or interest is still permissible. Juvenile adjudications do not count as criminal convictions for impeachment. Military convictions are admissible only if the offense is substantially equivalent to a Colorado felony. And unlike the federal rule, Colorado courts do not have discretion to bar a qualifying felony conviction. If it meets the statutory criteria, it comes in.⁸

Judicial Notice and Presumptions

Rule 201 governs judicial notice of adjudicative facts — facts “not subject to reasonable dispute” because they are either generally known within the court’s jurisdiction or capable of ready and accurate verification from unquestionable sources. A court may take judicial notice on its own at any stage and must take it if a party requests it and supplies the necessary information.¹

The effect depends on the type of case. In civil cases, the court instructs the jury to accept the noticed fact as conclusive. In criminal cases, the instruction is softer: the jury may, but is not required to, accept the fact as conclusive.¹

Rule 301 addresses presumptions in civil cases. A presumption shifts the burden of going forward with evidence to the opposing party but does not shift the ultimate burden of persuasion, which stays with the party that originally bore it.¹

Authentication and the Best Evidence Rule

Article IX (Rules 901–903) requires that evidence be authenticated or identified before admission. A party must produce enough evidence to support a finding that the item is what the party claims. Rule 902 lists categories of self-authenticating documents, such as certified public records and official publications, that need no extrinsic evidence of authenticity. Rule 903 eliminates any requirement that a subscribing witness testify to authenticate a document unless a statute specifically demands it.⁹

Article X (Rules 1001–1008) sets out the best evidence rule, which generally requires the original of a writing, recording, or photograph to prove its contents. Rule 1003 allows duplicates unless a genuine question is raised about the original’s authenticity or it would be unfair to admit the duplicate. Rule 1004 permits other evidence of the contents when the original has been lost or destroyed, cannot be obtained by judicial process, is in an opponent’s possession and not produced, or relates to a collateral issue.⁹

How the Rules Get Amended

The Colorado Supreme Court promulgates and amends the rules through a formal rule-change process. A standing Rules of Evidence Committee reviews proposed changes and recommends amendments to the Court.¹⁰

The most recent set of amendments, Rule Change 2025(05), was adopted by the Court en banc on January 16, 2025, and took effect immediately. It touched 21 rules across multiple articles (Rules 104, 404, 411, 602, 603, 604, 606, 607, 610, 611, 612, 613, 615, 706, 801, 803, 804, 806, 902, 1004, and 1007). The changes were primarily linguistic, replacing gendered pronouns with gender-neutral terminology throughout; references to “he” or “him,” for example, became “the accused,” “the witness,” “the declarant,” or “that party” as appropriate.¹¹¹²

1
Colorado Office of Rule & Policy Counsel. Colorado Rules of Evidence
2
H. Michael Steinberg Law Office. Colorado Rules of Evidence Part 2
3
Colorado Judicial Branch. Rule Change 2007-13
4
Casemine. People v. Shreck, No. 00SA105
5
Colorado Judicial Branch. People v. Martinez, 2024 CO 69
6
Justia. Colorado Revised Statutes Section 13-90-107
7
Colorado Judicial Branch. Rule Change 2016-03
8
Justia. Colorado Revised Statutes Section 13-90-101
9
Colorado Bar Association. Evidence in Colorado: A Practical Guide
10
Colorado Judicial Branch. Supreme Court Committees
11
Colorado Judicial Branch. Rule Change 2025(05)
12
Colorado Judicial Branch. Rule Change 2025(05) – Full Text