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- Introduction
- “Vehicle” and “Motor Vehicle”
- “Drive”
- “Drugs”
- “Legal Limit”
- Open Container
- Driving Under the Influence (DUI)
- Driving Under the Influence Per Se (“DUI Per Se”)
- Driving While Ability Impaired (DWAI)
- Second and Subsequent Offenses
- Underage Drinking and Driving (“UDD” or “Baby DUI”)
- Strict Liability
- Juveniles and Minors
- Evidence of Impairment
- Standardized Field Sobriety Tests (SFSTs)
- Drug Recognition Experts (DREs)
- Expressed Consent
- Breath Tests
- Blood Tests
- Prima Facie Case Requirement
- Preparing for Trial
- Voir Dire
- Expert Testimony
- Proving Chain of Custody
- Double-Refusals
Horizontal Gaze Nystagmus
Your officer conducting the HGN test must be endorsed and testify as an expert in HGN. Use the qualifications portion of your direct examination to build up the trustworthiness of the officer’s testimony before tendering them as an expert.
Example HGN Direct Examination Outline
Qualifications
What education do you have that qualifies you to testify as an expert in administering the Horizontal Gaze Nystagmus standard field sobriety test?
Related training?
Related experience?
Do you have any other accomplishments, such as certifications, awards, or memberships that qualify you as an expert in administering the Horizontal Gaze Nystagmus standard field sobriety test?
[Tender as Expert in administering and interpreting the Horizontal Gaze Nystagmus standard field sobriety test]
HGN in General
What is the HGN test? What is its purpose?
What is HGN? Why is this an important test in impaired driving cases?
Has the HGN test been field-validated as a reliable and accurate indicator of impairment? How many times? In Colorado?
What does the HGN test look like? How is it done? What are the steps?
[Consider introducing exhibit: IACP/NHTSA HGN Demonstration Video]
What is a “clue” and why is it important?
What are the different clues on this test?
This Case
Did you perform an HGN test in this case?
How did you perform the test? What specifically did you do?
What clues did you observe?
Breath Results
The portion of your direct examination introducing the results of the breath test should focus on the officer’s compliance with CDPHE’s rules and procedures for the I-9000.
Unless you or your colleagues are confident that your judge will not require you to endorse and qualify your officer as an expert in order to admit the results of the breath test, the safest approach at this time is to endorse and qualify the officer as an expert in the administration of the I-9000. See People v. Ambrose, 490 P.3d 822 (Colo. App. 2020) (“We acknowledge that [the officer’s] opinion is arguably an expert opinion because it was based on specialized training that he received in the operation of the I-9000.”).
If you choose to endorse and qualify your officer as an expert, do not qualify the officer as anything other than an expert in the administration of the I-9000. Most police officers are not experts in the I-9000 technology or “breath testing” generally. If you endorse them too broadly, you will open your officer up to seemingly reasonable defense questions the officer will not be able to answer.
Regardless of whether you qualify your officer as an expert, you’ll want to elicit from your officer their qualifications to administer breath tests using the I-9000, have them explain CDPHE’s rules and procedures, and then have them explain how they complied with these rules and procedures.
Example Breath Test Direct Examination Outline
Qualifications
What education do you have [that qualifies you to testify as an expert] in administering breath tests using the Intoxilyzer 9000?
Related training?
Related experience?
Do you have any other accomplishments, such as certifications, awards, or memberships that qualify you as an expert administering breath tests using the Intoxilyzer 9000?
[Tender as expert in administering breath tests using the Intoxilyzer 9000]
I-9000 in General
What is the Intoxilyzer 9000?
How were you trained to use it? What are the specific steps to using it?
What is the purpose of the 20-minute deprivation period? What are you looking for? What happens if you observe those things?
What is the purpose of testing the device before using it? How do you know the device is working correctly?
How do you know the result of a breath test? What do you do once you have a breath result?
Does the device print out anything when you are using it? What is the purpose of each printout? Do you retain these printouts? Why? Are you able to manipulate or alter these printouts in any way? Does the machine print them out for you?
This Case
How did you test the defendant’s breath in this case? What specific steps did you take? Did you follow all the steps you were trained and are required to follow? If you deviated, why did you deviate? Do you expect that deviation would impact the results? Why or why not?
Was the device working correctly? How do you know?
Did you observe the defendant for 20 minutes prior to administering the test? Did you observe anything that would require you to restart that period?
Tell the jury exactly how you administered the breath test portion of the test to the defendant. Did you hear and see the defendant breathe out? What did that look and sound like?
Did you observe any issues with the defendant breathing into the machine?
Did the machine record a result? Did you see it on the machine before the printout?
What was the result?
Did the machine also print out the result?
[Consider admitting and publishing the copy of the results page]
What other information did the machine print for purposes of documentation?
[Consider admitting and publishing the other printouts]
Officer, based on these printouts, do you have any reason to doubt the results of the machine in this case? If not, why not?
You don’t need to admit the printouts, but if you choose to use them, the printouts are admissible as non-hearsay, machine-generated documents. See C.R.E. 801 (defining hearsay as the out-of-court declarations of a human); People v. Hamilton, 452 P.3d 184, 192 (Colo. App. 2019) (holding that machine-generated documents are not hearsay because there is no declarant). The cases holding that breath test results are admissible could also be interpreted as permitting the admission of the machine printouts themselves. See, e.g., Thomas v. People, 895 P.2d 1040, 1045–46 (Colo. 1995) (“Once a prima facie showing is made that the testing device was in proper working order and was properly operated by a qualified person, and that the test was administered in substantial compliance with department of health regulations, the test results are admissible.”) The certificate page itself is admissible pursuant to § 42-4-1303. People v. Ambrose, 506 P.3d 57, 72 (Colo. App. 2021)
Blood Results
Although CBI lab reports are, by statute, admissible at trial without the testimony of a lab technician, any and all forensic toxicologists who conduct any portion of the testing of the defendant’s blood must be called as a witness when the defendant requests so at least 14 days before trial. § 16-3-309(5). Further, absent an express waiver by the defendant, the witness must testify. See Phillips v. People, 443 P.3d 1016, 1026 (Colo., 2019) (holding the defendant cannot inadvertently waive the 6th amendment right to confront a witness). In short, do not presume you can admit a laboratory report in lieu of the author’s testimony unless you have a written waiver from defense counsel.
Example Forensic Toxicologist Direct Examination Outline
Qualifications
What education do you have that qualifies you to testify as an expert in forensic toxicology?
Relevant training?
Relevant experience?
Do you have any other accomplishments, such as certifications, awards, or memberships that qualify you as an expert in forensic toxicology?
[Tender as Expert in forensic toxicology]
Forensic Toxicology in General
What is forensic toxicology?
How does a forensic toxicologist test blood for the presence of alcohol or drugs?
What kind of sample do you need?
How do you receive that sample?
What procedures are used to ensure the sample has not been tampered with?
Does the blood need to be refrigerated for forensic toxicology purposes? Why not?
How long does a sample last? How quickly must a sample be tested to ensure the accuracy of the results?
What substances can you test for?
How common is this kind of testing?
What are the specific steps involved in testing for [substance]?
This Case
What, if anything, do you know about the facts of this case?
Did you test the blood in this case?
What, specifically, did you do? Please explain how you did that, exactly.
Did you test for anything else? If not, why not?
Was testing complete after this? If not, why not? If not, what else remained?
What were the results of your tests?
What do those results mean? Are they consistent with impairment?
Caution About Using These Examples
The above example direct examination outlines are designed help you understand and visualize how a direct examination of an expert might be done in a standard impaired driving case. The outlines are only examples. It is your responsibility to develop direct examinations for your experts tailored to the specific facts and issues in your case. When in doubt, consult a more experienced colleague.
Resources
CDAC Videos
Admitting Test Results from the I-9000
Using Studies in Court: Expert Witness Testimony
Colorado Resources
Preparing for Expert Testimony: DREs on FTN
Preparing for Expert Testimony: Non-DREs on MRB
Preparing for Expert Testimony DREs on MRB
National Resources