CO · rules
CRE 701
Opinion Testimony by Lay Witnesses
If the witness is not testifying as an expert, the witness’ testimony in the form of
opinions or inferences is limited to those opinions or inferences which are (a) rationally
based on the perception of the witness, (b) helpful to a clear understanding of the witness’
testimony or the determination of a fact in issue, and (c) not based on scientific, technical,
or other specialized knowledge within the scope of Rule 702.
History
(Federal Rule Identical.) Source: Entire rule amended and adopted June 20, 2002, effective July 1, 2002. COMMITTEE COMMENT This rule does not foreclose an owner from giving an opinion as to the value of his real property. Universal Insurance Company v. Arrigo, 96 Colo. 531, 44 P.2d 1020 (1935). ANNOTATION Law reviews. For article, ‘‘Opinion Testi- mony’’, see 22 Colo. Law. 1185 (1993). For article, ‘‘Rule 701: Admissibility of Opinion Testimony by Lay Witnesses’’, see 26 Colo. Law. 63 (Mar. 1997). For article, ‘‘Rules 701 and 702: Boundary Between Lay and Expert Opinion Testimony’’, see 34 Colo. Law. 53 (July 2005). For article, ‘‘Lay V ersus Expert Testimony: Does V enalonzo v. People Clarify the Law?’’, see 46 Colo. Law. 46 (Aug.-Sept. 2017). Lay testimony must be: (1) Rationally based on the perception of the witness; and (2) helpful to a clear understanding of the wit- ness’s testimony or the determination of a fact in issue. People v. Baird, 66 P.3d 183 (Colo. App. 2002). Lay witness may testify only to opinions or inferences that are (1) rationally based on the perception of the witness, (2) helpful to a clear understanding of the witness’s testimony or the determination of a fact in issue, and (3) not based on scientific, technical, or other special- ized knowledge within the scope of C.R.E. 702. People v. Russell, 2014 COA 21M, 338 P.3d 472, aff’d, 2017 CO 3, 387 P.3d 750; People v. Acosta, 2014 COA 82, 338 P.3d 472. In determining whether testimony is lay testimony or expert testimony, the trial court must look to the basis for the opinion. If the witness provides testimony that could be ex- pected to be based on an ordinary person’s experiences or knowledge, then the witness is offering lay testimony. If, on the other hand, the witness provides testimony that could not be offered without specialized experiences, knowl- edge, or training, then the witness is offering expert testimony. V enalonzo v. People, 2017 CO 9, 388 P.3d 868; Campbell v. People, 2019 CO 66, 443 P.3d 72. Establishment of qualifications to express opinion is question for trial court. The suffi- ciency of evidence to establish the qualifica- tions and knowledge of a witness to express an opinion based on physical facts he has observed is a question for the trial court, not subject to reversal unless clearly erroneous. People v. Gallegos, 644 P.2d 920 (Colo. 1982). Attorney’s opinion about client’s mental condition admissible. The trial court errs in refusing to permit an attorney to express his opinion, as a lay witness, on the question of whether his client suffered from an impaired mental condition at the time of his alleged com- mission of an offense. People v. Rubanowitz, 673 P.2d 45 (Colo. App. 1983). In a first-degree sexual assault trial, testi- mony of counselor consisting of general com- ments based on her observations of victim’s demeanor following alleged sexual assault was not inadmissible as amounting to a scientific diagnosis of rape trauma syndrome, as long as counselor did not use scientific terminology, discuss theory, or state an opinion as to whether she believed victim. People v. Farley, 712 P.2d 1116 (Colo. App. 1985), aff’d, 746 P.2d 956 (Colo. 1987). Lay opinion from police officer admitted where police officer testified he had been in- volved in law enforcement for fourteen years, had experience investigating burglaries of park- ing lot money depositories, and was familiar with the tools similar to those allegedly used in burglary of money depository. People v. Garcia, 784 P.2d 823 (Colo. App. 1989). Lay opinion from police officer admitted where police officer testified he had been in- volved in law enforcement for sixteen years and had never had a suspect test positive for gun residue and had never experienced a recovery of a latent fingerprint from a firearm. The testi- mony was relevant to show that the absence of gun-shot residue and fingerprint evidence was not necessarily exculpatory. People v. Theus- Roberts, 2015 COA 32, 378 P.3d 750. No plain error in allowing police officer to testify without qualifying him as an expert when the testimony was brief and cumulative of the testimony of experts who had already testi- fied, in detail and without objection, about why gun-shot residue or latent fingerprint tests might be negative. People v. Theus-Roberts, 2015 COA 32, 378 P.3d 750. Police officer may offer lay testimony if based on his or her perceptions and experi- ences but does not require specialized training or education. People v. Tallwhiteman, 124 P.3d 827 (Colo. App. 2005). Lay opinion from detective stating he rec- ognized defendant on a surveillance video- tape was admissible, regardless of the fact that defendant’s appearance had not changed and the jury was allowed to view the videotape. The court held the detective’s testimony was ratio- nally based on his knowledge of the defendant’s appearance and that, since the defendant’s iden- tity was at issue in the trial, the detective’s testimony was helpful to a clear understanding of a fact at issue. People v. Robinson, 908 P.2d 1152 (Colo. App. 1995), aff’d, 927 P.2d 381 (Colo. 1996). Lay opinion of crime scene technician ad- mitted where the technician testified to the lo- cation of bullet holes and the paths of the bul- lets. The holes and paths of the bullets were evident from photographs. Technician did not perform any experiments or reconstruct the in- cident, therefore his testimony did not require any specialized or scientific knowledge to un- derstand. People v. Caldwell, 43 P.3d 663 (Colo. App. 2001). Detective’s computer-related testimony was lay testimony because it was not based upon specialized knowledge of computers or technology. Detective’s testimony was derived from plugging a flash drive into her computer and right-clicking on the image file to view the file’s properties and then reporting on what she observed without interpreting those observa- tions. While this requires basic computer com- petency, it is within the realm of knowledge of ordinary people who use computers in everyday life. People v. Froehler, 2015 COA 102, 373 P.3d 672. Allowing police officer’s testimony regard- ing use of glass pipe and torch lighter to smoke methamphetamine not plain error. People v. Malloy, 178 P.3d 1283 (Colo. App. 2008). Detective’s testimony about Facebook was lay testimony where the detective’s under- standing of Facebook and its features was based on information from his investigation and expe- rience or knowledge common among ordinary people using, or considering the use of, Face- book. People v. Glover, 2015 COA 16, 363 P.3d 736. Police officer’s interpretation of her con- versation with defendant was not expert tes- timony. The testimony was not based on spe- cialized skills but rather the ability to interpret a conversation in which officer took part, a pro- cess of reasoning familiar in everyday life. People v. Douglas, 2012 COA 57, 296 P.3d 234. Officers’ testimony about tracing the physical address of an email sender from an internet protocol address was improperly ad- mitted as lay testimony. People v. Garrison, 2017 COA 107, 411 P.3d 270. Trial court improperly admitted police of- ficer testimony as lay testimony that was ac- tually expert testimony, but the error was harmless. Agent’s testimony regarding the use of an electronic scale for drug dealing was based on his training and experience, therefore, it was expert testimony. Agent’s testimony re- garding the price range for drugs, amounts for personal use, and drug code words was also based on training and experience. The over- whelming evidence of defendant’s guilt made the error harmless. People v. Dominguez, 2019 COA 78, 454 P.3d 364. Officer’s testimony about which part of the marijuana plant is used to make edibles and whether drug dealers commonly main- tain separate production and distribution centers was improperly admitted as lay testi- mony. The testimony was based on the officer’s specific experience as a police officer and is not the type of information that an average citizen would be expected to know. Admitting the evi- dence did not constitute plain error since the prosecution also presented expert testimony on the same points. People v. Douglas, 2015 COA 155, 412 P.3d 785. Officer’s testimony identifying plants in defendants’ home as marijuana improperly admitted as lay testimony. The officer’s ability to identify marijuana plants was based exclu- sively on his specialized knowledge as a police officer, and therefore he should have been quali- fied as an expert before rendering his opinion. The error was harmless since the defendant pre- sented a medical marijuana affirmative defense, admitting to possessing the marijuana plants. People v. Douglas, 2015 COA 155, 412 P.3d 785. Officer’s testimony that marijuana edibles are typically candies, sodas, brownies, and butter was properly admitted as lay testi- mony. An ordinary citizen could reasonably have come to such an opinion based on a pro- cess of reasoning familiar in everyday life. People v. Douglas, 2015 COA 155, 412 P.3d 785. Police officer’s testimony concerning wit- ness’s body language was permissible lay tes- timony. While the police officer referred to his training and experience, he drew an inference that an ordinary person could have drawn based on everyday experience and knowledge. People v. Murphy, 2021 CO 22, 484 P.3d 678. A lay witness may testify concerning the identity of a person depicted in a surveillance photograph if there is some basis for conclud- ing that the witness is more likely to identify the defendant from the photograph than the jury is. Robinson v. People, 927 P.2d 381 (Colo. 1996). Lay opinion testimony of analyst from di- vision of insurance that petitioner’s income was not misrepresented admitted when she reviewed documents already before the jury and she based her testimony on her common tax knowledge and her experience as an insurance analyst. Hock v. New Y ork Life Ins. Co., 876 P.2d 1242 (Colo. 1994). Lay opinion of analyst from division of insurance regarding petitioner’s mental health admissible where testimony was based upon documentation analyst received as well as a personal meeting with the petitioner, and was supported by other evidence. Even if the testi- mony was inadmissible lay opinion, admission of testimony was cumulative, corrected by a limiting instruction, and harmless. Hock v. New Y ork Life Ins. Co., 876 P.2d 1242 (Colo. 1994). Lay opinion testimony is admissible to prove drug-induced intoxication. There is no basis to distinguish lay testimony regarding al- cohol-induced intoxication from lay testimony regarding drug-induced intoxication, as long as the proper foundation has been laid. People v. Souva, 141 P.3d 845 (Colo. App. 2005). Lay opinion testimony of witnesses, includ- ing minors, admissible to identify the sub- stance provided to them by defendant was marijuana. The witnesses described prior ex- periences with marijuana and based their iden- tification on its appearance, taste, and distinc- tive smell. These matters did not require any technical or specialized knowledge that would fall within the scope of C.R.E. 702. Accord- ingly, the minors established a proper founda- tion for their identification testimony. People v. Graybeal, 155 P.3d 614 (Colo. App. 2007). A person may testify as a lay witness only if his or her opinions or inferences do not require any specialized knowledge and could be reached by any ordinary person. To deter- mine whether an opinion is one ‘‘which could be reached by any ordinary person’’, courts consider whether ordinary citizens can be ex- pected to know or to have certain experiences. In this case, although the officer had experience with photo arrays that an ordinary person would not, the officer’s opinion could have been reached by an ordinary person. People v. Rincon, 140 P.3d 976 (Colo. App. 2005). There is no requirement that chemical tests be administered or that expert testimony be of- fered to bolster such lay identification testi- mony. People v. Graybeal, 155 P.3d 614 (Colo. App. 2007). Trial court inappropriately admitted lay testimony of investigating police officer as to experimentation with respect to and recon- struction of an incident without qualifying the officer as an expert witness. The officer’s testimony involved more than common experi- ence and required practical knowledge of a sci- entific, technical, or specialized nature. Admis- sion of the testimony constitutes harmless error, however, and does not require reversal. People v. Stewart, 55 P.3d 107 (Colo. 2002). Trial court erred in admitting police offi- cer’s testimony that did not result from a process of reasoning familiar in everyday life. The testimony was not proper lay opinion but rather was expert testimony presented in the guise of lay opinion. The error in admitting the testimony did not so undermine the fundamen- tal fairness of the trial as to cast serious doubt on the reliablity of the conviction. People v. McMinn, 2013 COA 94, 412 P.3d 551. Trial court improperly admitted as lay tes- timony police officer’s testimony about the meaning of the term ‘‘sherm’’. The testimony relied on the officer’s specialized training and experience as a police officer. People v. Bryant, 2018 COA 53, 428 P.3d 669. But the testimony did not have a substantial influence on the verdict or impair the fairness of the trial. People v. Bryant, 2018 COA 53, 428 P.3d 669. Trial court improperly admitted expert testimony of police officers concerning meth- amphetamine amounts, production chemi- cals, and manufacture under the guise of lay testimony. The testimony required specialized knowledge and training and, thus, was subject to the expert witness requirements of C.R.E. 702. People v. V eren, 140 P.3d 131 (Colo. App. 2005). Trial court abused its discretion by allow- ing detective to testify as a lay witness re- garding blood spatter and blood transfer. De- tective’s testimony had the hallmarks of expert testimony, but detective had not been qualified as an expert. Detective testified about his exten- sive experience investigating cases involving blood; detective used and defined technical terms; detective testified not based on his per- sonal knowledge or investigation of the case; and the prosecutor advised the court that detec- tive was testifying as to his training and expe- rience. People v. Ramos, 2012 COA 191, 396 P.3d 21, aff’d, 2017 CO 6, 388 P.3d 888. Trial court abused its discretion when it allowed a witness to testify about grooming as it relates to a sexual predator’s methods of acquiring victims without qualifying that witness as an expert. An ordinary citizen could not be expected to possess the experience, skills, or knowledge required to understand the concept of grooming as it relates to sexual pre- dation. People v. Romero, 2017 CO 37, 393 P.3d 973. Court abused its discretion in admitting some lay opinions from mental health pro- viders who had not been properly noticed as experts by the prosecution. Some of the opin- ions were expert opinions improperly admitted under the guise of lay opinion testimony. The improper testimony related to symptoms of spe- cific mental illness and opinions about whether defendant suffered from mental illness. The evi- dence relied upon the witness’ specialized knowledge and training and, therefore, went beyond the bounds of lay opinion. The error in this case was harmless since there was ample evidence in addition to the improperly admitted opinions. Dunlap v. People, 173 P.3d 1054 (Colo. 2007), cert. denied, 552 U.S. 1105 (2008). Lay opinion from alleged murder victim’s coworker who heard abusive statements made by defendant to victim found admis- sible and the coworker could make character- ization of such statements as a part of the testi- mony. People v. Hulsing, 825 P.2d 1027 (Colo. App. 1991). Admission of the opinion testimony of lay witnesses on the issue of causation does not constitute reversible error. Herrera v. Gene’s Towing, 827 P.2d 619 (Colo. App. 1992). Forensic interviewer’s testimony properly admitted. Testimony was not expert opinion evidence but rather an opinion based on obser- vation. People v. Tillery, 231 P.3d 36 (Colo. App. 2009), aff’d on other grounds sub nom. People v. Simon, 266 P.3d 1099 (Colo. 2011); People v. Marsh, 396 P.3d 1 (Colo. App. 2011), aff’d, 2017 CO 10M, 389 P.3d 100. Lay witness testimony that defendant was very ‘‘guilty-looking’’ immediately after the incident was not improper testimony. The witness’s statement was not that defendant was guilty or even that the witness believed that a crime had been committed, but statements de- scribing the witness’s rational perception of the defendant’s actions and demeanor after the al- leged event. Although the witness used the term ‘‘guilty’’, she was clearly not opining on whether the defendant was legally guilty, and the prosecutor’s questions as to what the wit- ness meant were phrased to elicit a factual rather than ‘‘legal’’ response. People v. Acosta, 2014 COA 82, 338 P.3d 472. A lay witness may state an opinion about another person’s motivation or intent only if the witness had sufficient opportunity to observe the person and to draw a rational conclusion about the person’s state of mind; an opinion that is speculative or not based on personal knowl- edge is not admissible. People v. Jones, 907 P.2d 667 (Colo. App. 1995). The trial court did not abuse its discretion in allowing a counselor from the detoxification facility at which the defendant allegedly com- mitted a sexual assault to state an opinion as to whether the sexual encounter was consensual, since the testimony was based on the counsel- or’s own observations. The trial court appropri- ately allowed the counselor to testify as to whether the victim was in an unconscious state at the time of the assault and to testify as to whether the defendant’s actions constituted a sexual assault. People v. Hoskay, 87 P.3d 194 (Colo. App. 2003). A lay witness may testify as to the substan- tial similarity between shoeprints found in connection with a crime and the defendant’s shoes if the witness’s conclusions are based on measurements or peculiarities in the prints that are readily recognizable and within the capabili- ties of a lay witness to observe. People v. Vigil, 2015 COA 88M, 459 P.3d 553, aff’d, 2019 CO 105, 455 P.3d 332. Officer’s testimony that defendant’s shoes visually matched the photos of the shoe prints taken at the crime scene based on the identical emblems and similar size was proper lay testimony. Because a comparison of a shoe and an imprint left in the dirt by a shoe based on the size of each and a visual compari- son of an emblem on the sole of a shoe is not beyond the capability of an ordinary person without specialized training or experience of any kind, the testimony was not expert testi- mony but rather lay testimony. Vigil v. People, 2019 CO 105, 455 P.3d 332. Peace officer’s testimony that he believed the defendant was the person in the security video footage was lay testimony not expert testimony. Recognizing people in videos or photographs is something ordinary people do all the time without specialized knowledge, expe- rience, or training. People v. Grant, 2021 COA 53, 492 P.3d 345. Where the witness was not qualified as an expert and the witness had no personal expe- rience with the maintenance expenses on the property, evidence presented as to the amount of future maintenance expenses was legally in- sufficient. Pomeranz v. McDonald’s Corp., 843 P.2d 1378 (Colo. 1993). Applied in People v. Nhan Dao V an, 681 P.2d 932 (Colo. 1984); Cheney v. Hailey, 686 P.2d 808 (Colo. App. 1984); Witcher v. Canon City, 716 P.2d 445 (Colo. 1986); People v. Col- lins, 730 P.2d 293 (Colo. 1986); People v. Sandoval v. Birx, 767 P.2d 759 (Colo. App. 1988); Pyles-Knutzen v. Bd. of County Comm’rs, 781 P.2d 164 (Colo. App. 1989); Graham v. Lombardi, 784 P.2d 813 (Colo. App. 1989); People v. Caldwell, 43 P.3d 663 (Colo. App. 2001).
Provenance
- Source
- content.leg.colorado.gov
- Retrieved
- 2026-09-15
- Edition
- 2026-09-15
- Content hash
a7a35fda1362928ff62526801ff77ab1b97cd4a6ea6a00e02261f6fd354b32fd
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