STATE OF MINNESOTA
IN COURT OF APPEALS
A15-1984
State of Minnesota,
Respondent,
vs.
Shane Lee Olson,
Appellant.
Filed December 5, 2016
Affirmed
Ross, Judge
Sherburne County District Court
File No. 71-VB-15-3373
Lori Swanson, Attorney General, St. Paul, Minnesota; and
Derek T. Archambault, Hawkins & Baumgartner, P.A., Anoka, Minnesota (for respondent)
John D. Ellenbecker, St. Cloud, Minnesota (for appellant)
Considered and decided by Cleary, Chief Judge; Worke, Judge; and Ross, Judge.
SYLLABUS
A police officer’s controlled testing of a handheld laser speed-measuring device to
establish that it is accurately measuring distance to a stationary object satisfies the
foundational external-test requirement of Minnesota Statutes section 169.14, subdivision
10(a) (2014), allowing the district court to admit into evidence the officer’s testimony of
the device’s speed readings.
OPINION
ROSS, Judge
A police officer used a handheld laser device and clocked Shane Olson’s car at 70
miles per hour in a 55-mile-per-hour zone. Olson challenged the ticket in court and objected
to the admission of the officer’s testimony of his speed. He argued that the officer’s external
testing of the laser unit failed to verify its reliability because the officer’s testing proved
only that the unit accurately measures distance, and speed depends on an accurate measure
of both time and distance. The district court overruled the objection and found Olson guilty.
Because the officer’s external test verified not only that the laser unit was measuring
distance accurately but also implicitly verified that it was measuring time accurately, the
district court did not abuse its discretion by admitting the officer’s testimony of the speed-
device evidence, and we affirm.
FACTS
Elk River police officer Andrew Zabee ticketed Shane Olson for speeding in July
2015. Officer Zabee testified at Olson’s bench trial that Olson’s car was traveling in a 55-
mile-per-hour zone when the officer’s handheld laser device indicated that Olson was
moving at 70 miles per hour. Olson objected to the officer’s testimony, contending that it
lacked a proper evidentiary foundation, and the district court sustained the objection. The
prosecutor questioned Officer Zabee further, and the officer testified that he was trained to
use the laser device, that his car was stationary when he encountered Olson’s car, that he
pointed the laser device out his open window to avoid any distortion, and that the weather
conditions were suitable for interference-free measurements by the device.
2
Olson again objected for lack of foundation, arguing that the officer’s testimony
failed to satisfy the external-test requirements of Minnesota Statutes section 169.14,
subdivision 10(a)(4), which allows an officer to testify to a reading from a speed-testing
device only if the officer first establishes that he performed an external test to verify that
the device was functioning reliably. The district court asked Officer Zabee, “Are there any
external tests done on this laser that you’re aware of?” The officer answered, “No.” The
district court implicitly agreed with Olson that the state had not laid the proper testimonial
foundation.
The prosecutor questioned Officer Zabee again. The officer testified that the device
ran its own internal test when he activated it. He then performed an external “distance
check.” He explained that he successfully performed the distance check by targeting an
object at a known distance from the unit, triggering the unit, and verifying that the distance
displayed on the unit accurately matched the known distance. The district court then
accepted the officer’s testimony that the laser unit calculated Olson’s speed at 70 miles per
hour.
Olson cross-examined Officer Zabee. The officer admitted that he performed no
separate test to establish that the device accurately measures speed. Olson again raised his
foundational challenge and argued that the officer’s testimony did not satisfy the statute
because speed is calculated based on distance and time, not just distance. The prosecutor
argued that the state has “never been required to prove up some sort of accurate
measurement of time” for traditional radar units, so it need not prove time for the laser unit.
3
The district court held that Officer Zabee’s distance check satisfied the foundational
requirements for speed-device evidence. It reasoned that section 169.14, subdivision
10(a)(4), does not specify that an external test is required “for every different component
of whatever formula the device is using.” It found Olson guilty of speeding. Olson appeals.
ISSUE
Does the district court act within its discretion and in compliance with Minnesota
Statutes section 169.14, subdivision 10(a), when the court allows an officer to state a
defendant’s speed based on the reading indicated on a laser device that the officer
externally tested only for its ability to accurately measure distance to a stationary object?
ANALYSIS
Olson asks us to reverse based on the purportedly erroneous evidentiary ruling. We
review a district court’s evidentiary rulings for an abuse of discretion. State v. Chavez-
Nelson, 882 N.W.2d 579, 588 (Minn. 2016). We will reverse only if the appellant
establishes that the district court’s ruling reflects an abuse of discretion and that the ruling
prejudiced his substantial rights. Id. Olson argues specifically that the district court should
not have admitted Officer Zabee’s testimony that the laser device indicated that he was
traveling at 70 miles per hour because the officer did not sufficiently test the unit. We think
Olson is wrong on the law and the science.
Olson contends that the prosecutor failed to lay adequate foundation for the officer’s
laser-result testimony. The relevant statute imposes four conditions before a district court
may admit evidence of speed measured by a laser unit or other speed-measuring device:
(1) the officer operating the device has sufficient training to
properly operate the equipment;
(2) the officer testifies as to the manner in which the device
was set up and operated;
4
(3) the device was operated with minimal distortion or
interference from outside sources; and
(4) the device was tested by an accurate and reliable external
mechanism, method, or system at the time it was set up.
Minn. Stat § 169.14, subd. 10(a). The constitutionality of this legislative evidentiary
requirement is not contested here, but, relevant to our application of the statute, we have
held that “because [section] 169.14 complies with, rather than conflicts with, the rules of
evidence, it does not violate the separation-of-powers doctrine.” State v. Ali, 679 N.W.2d
359, 365 (Minn. App. 2004).
Olson argues that the state failed to satisfy the fourth element of the foundational
requirement—the completion of an external test “by an accurate and reliable external
mechanism, method, or system.” He is wrong for two reasons. The first is that the statute
does not require an external test to verify the precision of every component of a speed-
measuring device’s calculation of speed. The second is that, even if it did, a distance-
measurement check of a standard laser unit meets that requirement.
Caselaw regarding laser evidence is less developed than caselaw for radar evidence,
but we have observed that the admissibility of laser evidence is analogous to the
admissibility of radar evidence. Ali, 679 N.W.2d at 365. Police test traditional squad-car
radar devices externally without necessarily measuring the speed of a moving physical
object; they can verify the device’s accuracy by measuring the frequency of its radiating
waves as modulated by a calibrated, vibrating tuning fork. State v. Gerdes, 291 Minn. 353,
357–60, 191 N.W.2d 428, 431–33 (1971). Olson does not identify any case that requires a
more specific external test to satisfy subdivision 10(a)(4), and we have found none. See
5
State v. McDonough, 302 Minn. 468, 470, 225 N.W.2d 259, 260 (1975) (holding that radar
device’s internal tuning fork serves as an adequate check on accuracy of external tuning
fork); State, City of St. Louis Park v. Bogren, 410 N.W.2d 383, 385 (Minn. App. 1987)
(stating that “use of properly calibrated internal and external tuning forks serves [as] an
adequate test of radar accuracy”); State v. Dow, 352 N.W.2d 125, 127 (Minn. App. 1984)
(affirming admission of officer’s testimony of radar results when tuning fork and calibrated
speedometer on squad car were used to check radar’s accuracy). We have declared that the
purpose of testing the radar unit is to determine that the mechanism is generally operating
properly, not to determine that it is operating properly in every mode. State v. Pulos, 406
N.W.2d 75, 76 (Minn. App. 1987) (rejecting an argument that a radar device must be re-
tested every time it is shifted from “moving” to “stationary” mode). And as to a laser device
specifically, we rejected the argument that testing the device on a moving object is required
to satisfy the statute’s external-test condition. Ali, 679 N.W.2d at 366. Under the caselaw,
subdivision 10(a)(4) requires only that a device be tested by an “accurate and reliable”
external method before an officer may testify about its results. See id.
This caselaw about the admissibility of speed-device evidence—particularly our Ali
case—is informative. It teaches that we have never interpreted the statute so as to preclude
an officer’s speed-device-results testimony simply because the officer’s external testing
was not scientifically exhaustive. A defendant is of course free to attempt to impeach the
officer’s testimony by criticizing the imprecise testing methodology and consequently
calling the unit’s reliability into doubt. See Minn. R. Evid. 607 (“The credibility of a
witness may be attacked by any party . . . .”). But there is a substantial difference between
6
testimony that is insufficiently reliable to be convincing (an ultimate decision for the fact-
finder) and testimony that is insufficiently reliable merely to be admitted (a preliminary
decision of law for the court). This is where our reasoning in Ali is particularly useful.
Again, we explained that the legislative foray into evidentiary foundations for trial
testimony does not unconstitutionally cross the separation-of-powers line specifically
because the statute “complies with, rather than conflicts with, the rules of evidence” as to
foundational admissibility. Ali, 679 N.W.2d at 365. Olson essentially urges us to apply the
statute to prohibit an officer from testifying about the laser unit’s speed calculation unless
the officer’s earlier external testing covers every element of the unit’s speed calculation.
Not only does the express language of the statute (calling for “an accurate and reliable
external [testing] method”) not demand this sort of exhaustive testing, an exhaustive-
testing obligation would also far exceed the judicially developed foundational
requirements. Because we have already interpreted the statute as providing an admissibility
rule that is consistent with rather than more restrictive than judicial foundational
requirements for non-expert witnesses, we will not now interpret it as imposing a more
formidable admissibility prerequisite. The caselaw convinces us that the limited, external
distance test for proper laser-unit functionality clears the statutory hurdle even if a more
exacting and probative accuracy test is conceivable.
Officer Zabee’s testing of the device is at least such a sufficient test. Olson does not
argue that the officer’s external distance check was inaccurate or unreliable, only that some
additional test for time must also have been performed before the officer could testify to
what the device indicated about Olson’s speed. Olson does not propose an additional,
7
independent external test that would verify specifically the accuracy of the device’s use of
time. And we can think of none. We are convinced that he has failed to demonstrate that
the district court abused its discretion by admitting the evidence.
Olson’s argument also depends on a misunderstanding of the science of standard
laser devices. So even if Olson is correct that the statute requires an officer to complete an
external test of a laser unit for both time and distance before the officer may testify about
the device’s calculation of a defendant’s speed, still we reject his appeal. This is because,
as a matter of basic physics, Officer Zabee’s distance check necessarily tested for both
distance and time. And as such, the distance check is an “accurate and reliable external . . .
method” to measure an object’s speed.
Reviewing how now-customary laser devices work informs us that, when a laser
device accurately calculates distance, it necessarily is also accurately measuring time.
Olson correctly states that the accuracy of a speed calculation depends on the accuracy of
both a time and distance measurement. But he overlooks the fact that a laser device first
calculates an object’s distance from the device in order to calculate its speed. See 1
McCormick on Evidence § 204(D) (Kenneth S. Broun, ed., 7th ed., June 2016) (explaining
laser-based speed-measuring technology, stating that the physical principles the technology
relies upon are “eminently sound,” and referencing multiple jurisdictions that have
expressly accepted the general reliability of laser technology); see also Datta Sainath
Dwarampudi & Venkat Sai Vivek Kakumanu, Efficiency of a LiDAR Speed Gun, 1 Int’l J.
of Electrical, Electronics & Data Comm. 27, 27–28 (2013); Ryan V. Cox & Carl Fors,
Admitting Light Detection and Ranging (LiDAR) Evidence in Texas: A Call for Statewide
8
Judicial Notice, 42 St. Mary’s L.J. 837, 849 (2011); see cf. Ali, 679 N.W.2d at 364
(indicating that a district court taking judicial notice of the general reliability of laser
technology would not be an abuse of discretion).
Understanding how a laser device accurately calculates a known distance
establishes the reliability of its time measurement. A laser unit measures distance
specifically based on the constant speed of light and based on the time it takes for pulsed,
infrared light to reflect off the target and return to the device. See Efficiency of LiDAR at
28; Admitting LiDAR at 849. The device calculates distance by multiplying half the
reflection time by the invariable speed of light. See Efficiency of LiDAR at 28. Therefore if
a laser device measures a known distance to an object accurately, it must necessarily be
measuring the time taken for light to travel to and return from that object accurately. To
calculate the speed of the object if it were moving, the device would then divide the object’s
change in distance between pulses of light by the amount of time elapsed between those
same pulses. Id.; see also Admitting LiDAR at 849. And if the device’s measurement of
time is shown to be accurate as to its calculation of distance, there is no reason to assume
that its measurement of time would be inaccurate as to its calculation of speed.
Olson’s challenge is therefore met: because the laser unit was accurately calculating
distance, it was also accurately measuring time and speed. There was no need for the officer
to additionally test the pulse-interval component of the unit by also testing it on a moving
object. We recognize that one certainly could test the device on a moving object, like a car
with a verified speedometer, and that this additional test would bolster the trustworthiness
of the officer’s laser-results testimony. And we understand that the unit’s ability to
9
precisely and accurately calculate the time that lapses between each of its myriad pulses is
a necessary feature of its ability to accurately read a vehicle’s speed. But for the purposes
of the purely foundational statute bearing only on admissibility rather than scientific
certainty, the district court acts within its discretion by reasonably assuming that a properly
functioning laser unit that accurately applies time, distance, and speed in its calculations to
a stationary object continues to apply those same elements accurately in its speed
calculation of a moving object. Put another way, just as we liberally but reasonably
presume under the statute that a radar unit that accurately calculates sound frequency will
accurately calculate a car’s speed, Bogren, 410 N.W.2d at 385, and that a radar unit that
accurately calculates a car’s speed in stationary mode will accurately calculate a car’s speed
in moving mode, Pulos, 406 N.W.2d at 76, the statute allows the district court to presume
that a laser unit that accurately measures time when it calculates an object’s distance will
also accurately measure time when it calculates a car’s speed. We expressly declined to
require a moving-object laser test in Ali, and Olson’s scientific argument does not call that
holding into question.
We reject Olson’s argument that Officer Zabee’s external test failed to measure time
and that it therefore failed to meet the statutory admissibility requirements.
DECISION
The officer’s external distance check established that the laser device was accurately
measuring distance, and this necessarily indicated that the device was also accurately
measuring time and speed. The district court did not err by holding that the distance check
satisfied the requirements of section 169.14, subdivision 10(a)(4), and it did not abuse its
10
discretion by allowing the officer to testify that the laser device measured Olson’s speed at
70 miles per hour.
Affirmed.
11