Wednesday, December 7, 2016

Test of Laser That Establishes Accurate Measurement of Known Distance Satisfies Foundation Requirement For Introduction of Speed Evidence

State v. Olson, Minn.Ct.App., 12/5/2016.  An officer ticketed Mr. Olson for speeding, based upon the officer's use of a handheld laser device. Mr. Olson challenged the foundational reliability of the laser device; he said that Minn.Stat. 169.14, subd. 10(a)(4) allows an officer to testify about 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.  Because the officer had only - and half-assed at that according to Mr. Olson - tested the laser's distance measurement the statute's requirements hadn't been met.  That's because speed is a measurement of both distance and time, and the officer performed no tests to determine that the laser was accurately measuring time.  Instead, the officer limited his testing to measuring a known distance to a stationary object.

Whew.  

The court of appeals said that Mr. Olson didn't understand just how a laser works.  The court said that the laser measures distance "specifically based on the constant speed of light and based on the time it takes for a pulsed, infrared light to reflect off the target and return to the device.  If the laser gets a known distance right then necessarily it have got the time right as well.

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