Police speed-measurement equipment

What counts as speed-measurement equipment

Speed-measurement equipment is any instrument an officer relies on to establish a vehicle's speed, and it covers far more than the radar gun. The 2008 Speed Enforcement Program Guidelines published jointly by the National Highway Traffic Safety Administration (NHTSA) and the Federal Highway Administration (FHWA), document DOT HS 810 915, name radar as "the most common method of speed enforcement in the United States," and then describe five other methods in active use.

• Radar transmits a microwave beam and reads the Doppler shift (the change in frequency of a signal reflected from a moving object). It works "in either a stationary or moving vehicle mode," according to the guidelines.
• Lidar (light detection and ranging, the laser speed gun) times pulses of infrared light. The guidelines note that it "is not vulnerable to radio interference, is not detectable by radar detectors."
• Pacing means following a vehicle at a matched speed and reading a patrol speedometer that "needs to be accurately calibrated and certified."
• Average-speed computers time a vehicle between two marks a known distance apart. "The most common brand of average-speed computer technology is VASCAR," the guidelines state.
• Aircraft time vehicles between pavement markings while ground units make the stops; some agencies pair VASCAR with fixed-wing aircraft.
• Automated speed enforcement cameras use, in the guidelines' words, "a narrow-beam radar or LIDAR to measure speeds."

Visual estimation is not an instrument, yet the California Highway Patrol (CHP) manual states that "an estimated speed, based on the officer's judgment, is admissible in court." Radar speed signs, the roadside displays that show a driver's speed, measure speed but are traffic-calming devices, not enforcement equipment.

Handheld, in-car, stationary and moving

Radar divides into handheld units the officer aims and console units mounted in the patrol car with one or two antennas, and then by operating mode. NHTSA's conforming product list (CPL) marks each radar model with a mode code: "Mode 'S' refers to the stationary mode and mode 'M' refers to the moving mode." Moving radar must account for the patrol car's own speed, which adds errors that stationary operation avoids.

The mode code does not map neatly onto the physical form. The CPL lists some handhelds as stationary only (the Stalker II SDR, the Decatur Genesis GHD, Scout and Scout 2) and others as stationary and moving (the Stalker II MDR, the Kustom Falcon HR, the Kustom Directional Talon and the MPH Speed Gun Pro). Physical form comes from manufacturer price lists, not the CPL; MPH sells its SpeedGun Pro in "battery, stationary," "dash, moving" and "corded, stationary" versions.

Lidar has its own vocabulary. The CPL defines a lidar device as equipment that "determines target range and speed based on the time-of-flight of laser light pulses," and a lidar system as "a lidar device that incorporates additional equipment that is used to gather, process and/or record images." A handheld laser gun is a device; a laser gun with a camera that records the vehicle is a system. NHTSA training states that lidar "is currently designed for stationary operations only."

VASCAR is often mistaken for radar, but it emits nothing. NHTSA's May 1991 study of VASCAR-plus (HS-807 748) described its arithmetic as "Speed = Distance/Time" and found results supporting a tolerance of about 2 mph at the 90th percentile for timings of at least four seconds (stationary) or five seconds (moving). Pennsylvania classifies such equipment as nonradar.

Who approves police speed devices

No federal agency approves or certifies police radar for use. That is the single most common misunderstanding about this equipment, and the federal record is explicit about it. A NHTSA notice in the Federal Register of November 21, 2024 (89 FR 92281) recounts the history. Radar has been used to detect speeding motorists in the United States "since the late 1940s." In 1977 NHTSA entered an interagency agreement with the National Bureau of Standards' Law Enforcement Standards Laboratory to develop performance standards. NHTSA proposed rules for down-the-road (DTR) radar in December 1980, then "decided not to regulate."

Instead, NHTSA published model specifications in March 1982 (DOT HS 806 191) that states and localities "were free to adopt." In the late 1990s the International Association of Chiefs of Police (IACP), under a cooperative agreement with NHTSA, formed the Enforcement Technologies Advisory Technical Subcommittee to update the specifications and provide laboratory testing. That work produced the current radar specification, DOT HS 812 266 (April 2016). Lidar specifications were first published in February 1995 as DOT HS 808 214; the current version is DOT HS 809 811 (March 2013).

The conforming product list was the practical output of that system. In NHTSA's own words it is "a document of the National Highway Traffic Safety Administration ... listing which speed measuring devices are eligible for purchase using Federal highway safety grant funds." A listed model had been "tested and found to follow the established performance specifications that were in effect when the model was first placed on the CPL." The list adds that "Test results ... do not represent product endorsement," and that a listing "will be voided by any third-party modifications not specifically approved by the original equipment manufacturer."

Under NHTSA's Interim Administrative Guide (November 2016), a manufacturer submitted one production unit to a qualified laboratory, and any change to hardware, software or model name required retesting. Discontinued models stayed listed as "APPROVED BUT NO LONGER IN PRODUCTION."

IACP's exit and the end of the radar CPL

The IACP stepped back first. Its testing page states: "As of October 1, 2015, IACP will no longer oversee the speed measurement device testing program." Manufacturers then worked directly with independent laboratories, which the IACP names as the Institute of Police Technology and Management in Jacksonville, Florida, and San Diego State University. After the cooperative agreement ended, the subcommittee disbanded and NHTSA ran the CPL itself under the interim guide.

The 2024 notice then ended federal listing for radar. NHTSA said it would "discontinue" the DTR radar CPL, that "as of November 21, 2024 NHTSA will no longer perform CPL processing," and that "as of November 21, 2025 NHTSA will retire the CPL." The replacement is an industry-based verification program. Manufacturers, "at their expense," use verification bodies accredited to ISO/IEC 17065 (an international standard for organizations that certify products) to test radar against IEEE Std 2450-2019, a radar performance standard published November 5, 2019. Verified units carry a "Verification Mark" and appear on a verified product list kept by the program. The National Institute of Standards and Technology (NIST) down-the-road radar page, updated August 10, 2026, links one such program, operated by ASTM/SEI. This site has not confirmed which radar models, if any, appear on that verified list.

Two limits of the change matter. IEEE 2450 verification does not cover "Unmanned radar speed-measuring devices, automated speed enforcement, or DTR radar range measurements." And the notice addresses down-the-road radar only; it says nothing about lidar. NHTSA's CPL page still displayed a combined radar and lidar CPL dated September 15, 2025, when checked on October 29, 2026. The details of that list cited on this site come from a reading of the NHTSA page rather than a full reading of the PDF, and no source found states whether NHTSA will keep the lidar list long term. The current version can be checked on the NHTSA CPL page.

State approval lists and procurement

Because federal listing never amounted to approval for use, approval rests with the states, and practice varies widely.

Georgia's Rule 570-7-.05 approves "Speed detection devices listed in the annual administrative order issued by the Commissioner" and adds that "Also sanctioned are speed detection devices from the International Association of Chiefs of Police," with radar required to meet the listed specifications. The Georgia Department of Public Safety posted the November 28, 2022 NHTSA CPL as its "Approved Speed Detection Devices 2023." A later Georgia order was not located.

Pennsylvania goes further by statute. Under 75 Pa.C.S. § 3368, radar "may be used only as part of an automated speed enforcement system or by members of the Pennsylvania State Police." Municipal officers there use nonradar equipment. PennDOT publishes "Approved Speed-Timing Devices and Appointment of Maintenance and Calibration Stations" in the Pennsylvania Bulletin; the December 29, 2018 list (48 Pa.B. 8007) approved radar for the State Police in stationary mode only, including the Kustom Falcon HR and Eagle Plus, the Decatur Genesis-II Select, the Applied Concepts Stalker Dual and the MPH Ranger EZ. It also approved average-speed devices such as VASCAR-plus III and stopwatches by serial number. A newer list was not located.

Procurement contracts are a separate matter. New York's Office of General Services Award PGB 23348, which piggybacks on a Washington state NASPO ValuePoint contract and runs January 9, 2025 to August 31, 2027, lists Applied Concepts, DragonEye Technology, Kustom Signals, Laser Technology, MPH Industries, All Traffic Solutions and Traffic Logix as contractors. A contract sets who may sell to agencies; it does not approve a device for evidentiary use.

Calibration, certification and training

Calibration (the comparison of an instrument's readings against a known reference) happens at two levels: routine checks by the operator, and periodic certification by a laboratory or approved station.

Operator checks follow NHTSA training. A radar operator uses tuning forks (one fork for stationary mode, two for moving) and the unit's internal circuit test. A lidar operator runs a light test, a circuit check, a sight alignment test and fixed-distance and delta-distance tests. The CHP manual requires radar to be "calibrated and certified by an independent laboratory" and "calibrated and tested at the beginning and ending of each shift by certified radar officers," with logs kept for court.

Certification intervals are set by each jurisdiction, and they differ:

• Pennsylvania: radar "shall have been tested for accuracy within a period of one year prior to the alleged violation"; other devices within 60 days.
• California Highway Patrol: patrol speedometers calibrated "every 90 days or 30,000 miles using radar or a fifth wheel."
• NHTSA interim guide: laboratory retesting recommended every 36 months, as guidance rather than a requirement.

Operators are certified too. The NHTSA/FHWA guidelines describe radar or lidar training as commonly 40 hours or more, delivered by state academies, the IACP, the National Sheriffs' Association and Peace Officer Standards and Training (POST) bodies, and note that "In most jurisdictions recertification is required and conducted on an annual or biennial basis." On military installations, 32 CFR 634.27 requires radar operators to meet the host state's requirements and to recertify every three years or as state law prescribes.

The manufacturers and how they relate

The September 15, 2025 CPL names four makers of current-production radar: Applied Concepts, Inc. (which trades as Stalker Radar, Richardson, Texas), Decatur Electronics (Escondido, California), Kustom Signals (Lenexa, Kansas) and MPH Industries (Owensboro, Kentucky). It names six makers of current-production lidar: Applied Concepts, Dragon Eye Technology, Kustom Signals, Laser Technology, Inc. (Centennial, Colorado), MPH Industries and Unipar Services.

Four names on that list are fewer independent companies than they appear. MPD, Inc., a holding company in Owensboro, Kentucky, bought MPH Industries in 1988 and acquired Kustom Signals on November 4, 2014, with Kustom kept as a separate subsidiary. MPH's own history states that MPD has been 100 percent employee-owned through an employee stock ownership plan (ESOP) since 1997. In September 2025 Kustom described itself as "integrating with sister company MPH Industries" while keeping the brands distinct. The two are sister companies, not parent and subsidiary. MPH entered the laser market by purchasing Laser Atlanta in 2012.

The other makers stand apart. Decatur Electronics, founded in 1955 in Decatur, Illinois, was bought from D&K Engineering of San Diego by its managing partners in December 2022, and it sells lidar made by DragonEye Technology of Norcross, Georgia, rather than its own. Laser Technology, Inc. builds lidar only and has no radar on the CPL. Applied Concepts, founded in 1975, does not state its ownership on its company pages. "First" claims in this field come largely from the manufacturers, and some conflict: Kustom dates its first laser speed gun to 1990, while Laser Technology calls its 1991 20/20 Marksman "the market's first commercial speed laser." Both claims are recorded here; neither is confirmed by an independent source.

Frequently asked questions

Sources

• National Archives / Federal Register (NHTSA notice) — Federal Register notice, NHTSA, Docket NHTSA-2024-0074 (FR Doc. 2024-27130) (2024, PDF)
• NHTSA (hosted by Georgia Department of Public Safety) — Conforming Product List (CPL): Speed-Measuring Devices, November 28, 2022 (as posted by Geor… (2022, PDF)
• nhtsa.gov/document/conforming-product-list-cpl-speed-measuring-devices
• nhtsa.gov/sites/nhtsa.gov/files/documents/interim_admin_guide_-_nov_29_2016.…
• rosap.ntl.bts.gov/view/dot/16480/dot_16480_DS1.pdf
• legis.state.pa.us/WU01/LI/LI/CT/HTM/75/00.033.068.000..HTM
• chp.ca.gov/siteassets/policy/hpm/hpm-70.6/hpm-70.6-ch-7.pdf
• theiacp.org/resources/document/iacp-radarlidar-testing
• mphindustries.com/about-us/