Arizona: Independent Test Shows Speed Cameras Do Not Slow Drivers

The Newspaper
by The Newspaper
arizona independent test shows speed cameras do not slow drivers

The state of Arizona began deploying speed cameras on freeways last year for the stated purpose of slowing drivers. Scottsdale was the first jurisdiction in the state to use such cameras and issued $17 million worth of automated freeway tickets before the state took over the program. The city paid a local professor $75,000 to create a study to show that drivers had slowed. An expert in radar technology produced a report last month insisting that is not the case.

Craig Peterson is the founder of, a company that has performed independent evaluations of various types of radar and laser speed detection equipment for nearly two decades. Peterson performed an independent and simple test of Arizona’s photo radar program to verify whether drivers have actually slowed.

“Accurate statistics of accidents at camera locations won’t be available for some time yet, but now that scores of speed cameras and a fleet of 100 photo radar vans have been deployed, it certainly isn’t difficult to measure the cameras’ effect on freeway speeds,” Peterson explained.

Peterson set up his equipment on freeways in Glendale, Mesa, Prescott Valley and Star Valley. He used a Kustom Signals Pro Laser III lidar gun and LaserStat traffic survey software to measure speeds one-half mile before a speed camera and one-half mile after the camera during free-flow traffic. The sample included at least 200 measurements at each location using the speeds of cars in each travel lane. In all cases, Peterson strictly adhered to accepted engineering practices for performing a traffic speed study.

“Interestingly, the numbers from every site were nearly identical,” Peterson wrote. “Far from slowing traffic, the cameras had no effect on freeway speeds… Aside from a brief dab at the brakes by a few drivers in reaction to fixed speed cameras — frequently resulting in screeching tires from cars behind — most seemed oblivious to them. Hardly any slowed in reaction to the speed vans.”

The speed limit on the Loop 101 freeway is 65 MPH, although engineering guidelines suggest that limits be set at the 85th percentile speeds, the rate at which the vast majority of motorists safely travel. Peterson’s measurements found that the 85th percentile speed on the Loop 101 ranged from 70 MPH to 73.4 MPH at the original photo radar locations in Scottsdale. Before and after speeds were identical except by a statistically insignificant increase in the after speed at two locations.

The National Motorists Association, which opposes the use of speed cameras, was not surprised by the findings.

“Believing the claims of companies that sell photo enforcement equipment or municipalities that use this equipment is like believing any commercial produced by a company that is trying to sell you something,” the group explained on its website. “There is no independent verification that photo enforcement devices improve highway safety, reduce overall accidents, or improve traffic flow.”

Are Speed Cameras Effective? (, 7/8/2009)

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  • Ttacgreg Ttacgreg on Aug 12, 2009

    Of course speed control and slowing traffic down are most likely not the motive behind the cameras. Revenue is.

  • Bleach Bleach on Aug 12, 2009

    Chicagoland does not use fixed cameras, but some idiot vans. I got hit with a $400 ticket for going 67 in construction zone of 45mph. The day after I got the ticket I drove 50 through the zone. I can't count the number of people who gave me the finger or got in front of me to test emergency braking or wash their windshields. My experiment lasted for one day. Oh and the ticket came 6 weeks after the date of the violation, so who knows how many I could have out there.

  • Wolfwagen I would rather have an annual inspection that may catch something early or at least the driver can be informed of an impending issue. Government vs private is another issue and unscrupulous mechanics is another.On a slightly different topic is the inspection of salvage or rebuilt cars. In NYS it is strictly to ensure that stolen parts were not used to rebuild the vehicle. I would rather see an inspection to ensure that the vehicle has been properly put back together.
  • PeterPuck For years, Ford has simply reworked existing designs originating from Europe and Japanese manufacturers, not being capable of designing a decent car in the USA.What’s the last clean sheet design from the USA? The 1986 Taurus?And they still can’t manage to get things right.why is this? Are they putting all of the competent engineers and designers on the F150? Is woke diversification affecting them, as some rumours suggest? Are they rewarding incompetence?
  • Brandon What is a "city crossover"?
  • Tassos What was the last time we had any good news from Ford? (or GM for that matter?)The last one was probably when Alan Mulally was CEO. Were you even born back then?Fields was a total disaster, then they go hire this clown from Toyota's PR department, the current Ford CEO, Fart-ley or something.He claims to be an auto enthusiast too (unlike Mary Barra who is even worse, but of course always forgiven, as she is the proud owner of a set of female genitals.
  • Tassos I know some would want to own a collectible Mustang. (sure as hell not me. This crappy 'secretary's car' (that was exactly its intended buying demo) was as sophisticated (transl. : CRUDE) as the FLintstone's mobile. Solid Real Axle? Are you effing kidding me?There is a huge number of these around, so they are neither expensive nor valuable.WHen it came out, it was $2,000 or so new. A colleague bought a recent one with the stupid Ecoboost which also promised good fuel economy. He drives a hard bargain and spends time shopping and I remember he paid $37k ( the fool only bought domestic crap, but luckily he is good with his hands and can fix lots of stuff on them).He told me that the alleged fuel economy is obtained only if you drive it like a VERY old lady. WHich defeats the purpose, of course, you might as well buy a used Toyota Yaris (not even a Corolla).