Shreck hearing in Colorado

2026Standard of Review and Applicable Law ¶ 36 We review the admission of expert testimony “for an abuse of discretion and will reverse only when that decision is manifestly erroneous.” People v. Cooper, 2021 CO 69, ¶ 44 (quoting People v. Rector, 248 P.3d 1196, 1200 (Colo. 2011)). 13 ¶ 37 When determining whether expert testimony is admissible under CRE 702, district courts employ “a Shreck analysis, which requires that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the expert is qualified to opine on such matters; (3) the expert testimony will be helpful to

2026Standard of Review and Applicable Law ¶ 36 We review the admission of expert testimony “for an abuse of discretion and will reverse only when that decision is manifestly erroneous.” People v. Cooper, 2021 CO 69, ¶ 44 (quoting People v. Rector, 248 P.3d 1196, 1200 (Colo. 2011)). 13 ¶ 37 When determining whether expert testimony is admissible under CRE 702, district courts employ “a Shreck analysis, which requires that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the expert is qualified to opine on such matters; (3) the expert testimony will be helpful to

2026Standard of Review and Applicable Law ¶ 36 We review the admission of expert testimony “for an abuse of discretion and will reverse only when that decision is manifestly erroneous.” People v. Cooper, 2021 CO 69, ¶ 44 (quoting People v. Rector, 248 P.3d 1196, 1200 (Colo. 2011)). 13 ¶ 37 When determining whether expert testimony is admissible under CRE 702, district courts employ “a Shreck analysis, which requires that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the expert is qualified to opine on such matters; (3) the expert testimony will be helpful to

2026Standard of Review and Applicable Law ¶ 36 We review the admission of expert testimony “for an abuse of discretion and will reverse only when that decision is manifestly erroneous.” People v. Cooper, 2021 CO 69, ¶ 44 (quoting People v. Rector, 248 P.3d 1196, 1200 (Colo. 2011)). 13 ¶ 37 When determining whether expert testimony is admissible under CRE 702, district courts employ “a Shreck analysis, which requires that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the expert is qualified to opine on such matters; (3) the expert testimony will be helpful to

2025Accordingly, because the defense did not provide any substantive reason to question the reliability of Von Rentzell’s testing, the district court did not abuse its discretion when it determined that the general concerns raised did not warrant a Shreck hearing because those concerns went to the weight of Von 8 Rentzell’s testimony and not its admissibility.2 See Shreck, 22 P.3d at 78 (Concerns about an expert’s certainty can be resolved “by [v]igorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof,” not by excluding the expert’s testimony.)

2025Accordingly, because the defense did not provide any substantive reason to question the reliability of Von Rentzell’s testing, the district court did not abuse its discretion when it determined that the general concerns raised did not warrant a Shreck hearing because those concerns went to the weight of Von 8 Rentzell’s testimony and not its admissibility.2 See Shreck, 22 P.3d at 78 (Concerns about an expert’s certainty can be resolved “by [v]igorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof,” not by excluding the expert’s testimony.)

2011It is clear from the record that the trial court declined a Shreck hearing on shaken-baby syndrome because it appeared not to be an issue in the case. [7] Additionally, and alternatively, the trial court denied the request for a Shreck hearing on shaken-baby syndrome determining that the syndrome is recognized in Colorado as a reliable scientific principle, and that based on the evidence, arguments, and People v. Martinez, 74 P.3d 316 (Colo. 2003) (in which this Court examined the admissibility of shaken-baby syndrome testimony), [8] no Shreck hearing was required.

2011It is clear from the record that the trial court declined a Shreck hearing on shaken-baby syndrome because it appeared not to be an issue in the case. [7] Additionally, and alternatively, the trial court denied the request for a Shreck hearing on shaken-baby syndrome determining that the syndrome is recognized in Colorado as a reliable scientific principle, and that based on the evidence, arguments, and People v. Martinez, 74 P.3d 316 (Colo. 2003) (in which this Court examined the admissibility of shaken-baby syndrome testimony), [8] no Shreck hearing was required.

2021(Emphasis added.) ¶ 68 Mr. Ambrose also relies on counsel’s objection during trial to admission of the I-9000 certificate and the breath test results “as unreliable.” The People argue that this was insufficient to preserve Mr. Ambrose’s appellate argument that admission of the working order certificate violated his rights under the Confrontation Clause. 36 The trial court did not rule on the confrontation issue when it denied defense counsel’s motion for a Shreck hearing. ¶ 69 We acknowledge that a pretrial motion, like the one here, may preserve an evidentiary objection for appellate review “

2021(Emphasis added.) ¶ 68 Mr. Ambrose also relies on counsel’s objection during trial to admission of the I-9000 certificate and the breath test results “as unreliable.” The People argue that this was insufficient to preserve Mr. Ambrose’s appellate argument that admission of the working order certificate violated his rights under the Confrontation Clause. 36 The trial court did not rule on the confrontation issue when it denied defense counsel’s motion for a Shreck hearing. ¶ 69 We acknowledge that a pretrial motion, like the one here, may preserve an evidentiary objection for appellate review “

2026When, as here, the court “already has sufficient information to make specific findings under Shreck, a hearing is not necessary.” People v. Wilson, 2013 COA 75, ¶ 23 . ¶ 22 And, finally, Quintanilla also seems to argue that by denying him a Shreck hearing, the court failed to realize that the prosecution provided him with an older version of Miller’s source list.

2026When, as here, the court “already has sufficient information to make specific findings under Shreck, a hearing is not necessary.” People v. Wilson, 2013 COA 75, ¶ 23 . ¶ 22 And, finally, Quintanilla also seems to argue that by denying him a Shreck hearing, the court failed to realize that the prosecution provided him with an older version of Miller’s source list.

2026Huntoon v. TCI Cablevision of Colo., Inc., 969 P.2d 681, 690 (Colo. 1998). ¶ 17 To qualify an expert witness, “[a] trial court need not conduct a Shreck hearing if there is sufficient information to make an admissibility determination without one, but [it] must nonetheless address the testimony and make specific findings regarding its challenged admissibility.” Kutzly v. People, 2019 CO 55, ¶ 11 .

2026Huntoon v. TCI Cablevision of Colo., Inc., 969 P.2d 681, 690 (Colo. 1998). ¶ 17 To qualify an expert witness, “[a] trial court need not conduct a Shreck hearing if there is sufficient information to make an admissibility determination without one, but [it] must nonetheless address the testimony and make specific findings regarding its challenged admissibility.” Kutzly v. People, 2019 CO 55, ¶ 11 .

2018The 21 overarching concern of any Shreck analysis is the reliability and relevance of the scientific evidence, and we conclude, like other courts, that GPS evidence is sufficiently reliable to satisfy CRE 702. ¶ 44 We realize that Colorado’s standard for the admissibility of scientific evidence differs from the test laid out in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), and that other state rules of evidence may differ from CRE 702.

2013People v. Rector, 248 P.3d 1196, 1200 (Colo.2011)(citing Shreck, 22 P.3d at 77-79 ); see also Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 592-94 , 118 S.Ct. 2786 , 125 L.Ed.2d 469 (1998).

2013See id. ; see also Kumho Tire Co. v. Carmichael, 526 U.S. 137 , 141-42, 119 S.Ct. 1167 , 143 L.Ed.2d 238 (1999) (inquiry into whether testimony is based on scientific, technical, or "other specialized" knowledge should be flexible). ¶ 64 Based on the testimony at the Shreck hearing, the trial court made the following findings: ?

2013See id. ; see also Kumho Tire Co. v. Carmichael, 526 U.S. 137 , 141-42, 119 S.Ct. 1167 , 143 L.Ed.2d 238 (1999) (inquiry into whether testimony is based on scientific, technical, or "other specialized" knowledge should be flexible). ¶ 64 Based on the testimony at the Shreck hearing, the trial court made the following findings: ?

2026Id. ¶ 21 To be admissible, the prosecution “need not prove that the expert is undisputably correct,” only that “the method employed by the expert in reaching the conclusion is scientifically sound and that the opinion is based on facts which sufficiently satisfy Rule 702’s reliability requirements.” People v. Ramirez, 155 P.3d 371, 378 (Colo. 2007) (quoting Gallegos v. Swift & Co., 237 F.R.D. 633, 639 (D.

2026Id. ¶ 21 To be admissible, the prosecution “need not prove that the expert is undisputably correct,” only that “the method employed by the expert in reaching the conclusion is scientifically sound and that the opinion is based on facts which sufficiently satisfy Rule 702’s reliability requirements.” People v. Ramirez, 155 P.3d 371, 378 (Colo. 2007) (quoting Gallegos v. Swift & Co., 237 F.R.D. 633, 639 (D.

2026Standard of Review and Applicable Law ¶ 36 We review the admission of expert testimony “for an abuse of discretion and will reverse only when that decision is manifestly erroneous.” People v. Cooper, 2021 CO 69, ¶ 44 (quoting People v. Rector, 248 P.3d 1196, 1200 (Colo. 2011)). 13 ¶ 37 When determining whether expert testimony is admissible under CRE 702, district courts employ “a Shreck analysis, which requires that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the expert is qualified to opine on such matters; (3) the expert testimony will be helpful to

2026Standard of Review and Applicable Law ¶ 36 We review the admission of expert testimony “for an abuse of discretion and will reverse only when that decision is manifestly erroneous.” People v. Cooper, 2021 CO 69, ¶ 44 (quoting People v. Rector, 248 P.3d 1196, 1200 (Colo. 2011)). 13 ¶ 37 When determining whether expert testimony is admissible under CRE 702, district courts employ “a Shreck analysis, which requires that: (1) the scientific principles underlying the testimony are reasonably reliable; (2) the expert is qualified to opine on such matters; (3) the expert testimony will be helpful to

2026Huntoon v. TCI Cablevision of Colo., Inc., 969 P.2d 681, 690 (Colo. 1998). ¶ 17 To qualify an expert witness, “[a] trial court need not conduct a Shreck hearing if there is sufficient information to make an admissibility determination without one, but [it] must nonetheless address the testimony and make specific findings regarding its challenged admissibility.” Kutzly v. People, 2019 CO 55, ¶ 11 .

2026Huntoon v. TCI Cablevision of Colo., Inc., 969 P.2d 681, 690 (Colo. 1998). ¶ 17 To qualify an expert witness, “[a] trial court need not conduct a Shreck hearing if there is sufficient information to make an admissibility determination without one, but [it] must nonetheless address the testimony and make specific findings regarding its challenged admissibility.” Kutzly v. People, 2019 CO 55, ¶ 11 .

2026Id. ¶ 21 To be admissible, the prosecution “need not prove that the expert is undisputably correct,” only that “the method employed by the expert in reaching the conclusion is scientifically sound and that the opinion is based on facts which sufficiently satisfy Rule 702’s reliability requirements.” People v. Ramirez, 155 P.3d 371, 378 (Colo. 2007) (quoting Gallegos v. Swift & Co., 237 F.R.D. 633, 639 (D.

2026Id. ¶ 21 To be admissible, the prosecution “need not prove that the expert is undisputably correct,” only that “the method employed by the expert in reaching the conclusion is scientifically sound and that the opinion is based on facts which sufficiently satisfy Rule 702’s reliability requirements.” People v. Ramirez, 155 P.3d 371, 378 (Colo. 2007) (quoting Gallegos v. Swift & Co., 237 F.R.D. 633, 639 (D.

2025Accordingly, because the defense did not provide any substantive reason to question the reliability of Von Rentzell’s testing, the district court did not abuse its discretion when it determined that the general concerns raised did not warrant a Shreck hearing because those concerns went to the weight of Von 8 Rentzell’s testimony and not its admissibility.2 See Shreck, 22 P.3d at 78 (Concerns about an expert’s certainty can be resolved “by [v]igorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof,” not by excluding the expert’s testimony.)

2025Accordingly, because the defense did not provide any substantive reason to question the reliability of Von Rentzell’s testing, the district court did not abuse its discretion when it determined that the general concerns raised did not warrant a Shreck hearing because those concerns went to the weight of Von 8 Rentzell’s testimony and not its admissibility.2 See Shreck, 22 P.3d at 78 (Concerns about an expert’s certainty can be resolved “by [v]igorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof,” not by excluding the expert’s testimony.)

2025In this case, however, mother raised detailed and specific objections as to each prong of the Shreck analysis. 6 ¶ 16 To the contrary, the supreme court has made clear that Shreck and CRE 702 “govern[] the admissibility of all expert testimony in Colorado, including experience-based expert testimony.” Kutzly, ¶ 10 (emphasis added); see also People v. Douglas, 2015 COA 155, ¶ 75 (“In all cases, even where expertise is based on experience alone, the trial court must maintain its role as a gatekeeper to ensure that ‘specialized testimony is reliable, relevant, and helpful to the jury.’” (citation

2025In this case, however, mother raised detailed and specific objections as to each prong of the Shreck analysis. 6 ¶ 16 To the contrary, the supreme court has made clear that Shreck and CRE 702 “govern[] the admissibility of all expert testimony in Colorado, including experience-based expert testimony.” Kutzly, ¶ 10 (emphasis added); see also People v. Douglas, 2015 COA 155, ¶ 75 (“In all cases, even where expertise is based on experience alone, the trial court must maintain its role as a gatekeeper to ensure that ‘specialized testimony is reliable, relevant, and helpful to the jury.’” (citation

2021See, e.g., Venalonzo v. People, 2017 CO 9, ¶¶ 32-34 .

2021See, e.g., Venalonzo v. People, 2017 CO 9, ¶¶ 32-34 .

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020Marston has never disputed the point that Colorado trial courts regularly admit such evidence. 21 aff’d on other grounds, 886 A.2d 824 (Conn. 2005); Ruthardt, 680 A.2d at 356-60 (applying Shreck-like test; HGN test results admissible as evidence of impairment); Williams v. State, 710 So. 2d 24, 30-32 (Fla. Dist.

2020Marston has never disputed the point that Colorado trial courts regularly admit such evidence. 21 aff’d on other grounds, 886 A.2d 824 (Conn. 2005); Ruthardt, 680 A.2d at 356-60 (applying Shreck-like test; HGN test results admissible as evidence of impairment); Williams v. State, 710 So. 2d 24, 30-32 (Fla. Dist.

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020Marston has never disputed the point that Colorado trial courts regularly admit such evidence. 21 aff’d on other grounds, 886 A.2d 824 (Conn. 2005); Ruthardt, 680 A.2d at 356-60 (applying Shreck-like test; HGN test results admissible as evidence of impairment); Williams v. State, 710 So. 2d 24, 30-32 (Fla. Dist.

2020Marston has never disputed the point that Colorado trial courts regularly admit such evidence. 21 aff’d on other grounds, 886 A.2d 824 (Conn. 2005); Ruthardt, 680 A.2d at 356-60 (applying Shreck-like test; HGN test results admissible as evidence of impairment); Williams v. State, 710 So. 2d 24, 30-32 (Fla. Dist.

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2020See, e.g., Ballard v. State, 955 P.2d 931, 940 (Alaska Ct. App. 1998) (HGN evidence meets Frye test if results are offered to show a person has consumed alcohol and is potentially impaired), overruled on other grounds as recognized by Alvarez v. State, 249 P.3d 286 (Alaska 2011); State v. City Court, 799 P.2d 855, 859 (Ariz. 1990) (HGN test satisfies the Frye standard if offered only as evidence of impairment); State v. Commins, 850 A.2d 1074, 1080-81 (Conn. App. Ct. 2004) (HGN test evidence satisfied Daubert test), 4 As noted above, the prosecution cited several trial court decisions admittin

2019Id. at 953, 955, 957 . ¶ 35 Having considered the foregoing cases, we hold that the use of historical cell site data to determine the general geographic location of a cell phone is widely accepted as reliable and does not require a Shreck hearing.

2019Id. at 953, 955, 957 . ¶ 35 Having considered the foregoing cases, we hold that the use of historical cell site data to determine the general geographic location of a cell phone is widely accepted as reliable and does not require a Shreck hearing.