How to Create and Present Your Own Speed Survey

[lbk]

There seems to be a lot of negativity out here about doing your own survey, but I haven't heard anything substantive about why it's bad/wrong.

So, Huntington Beach sends police (i.e. non-engineers) out to collect the data which suggests that part doesn't require expertise. College-student agrees and says you need the expertise to "interpret" the data. Once the data is collected, it's just a bunch of speeds. the interpretation is finding the 85th percentile which is trivial.

Now, I personally have some additional detail so I can establish that my methods are rigorous and an improvement on the existing traffic survey, but please someone tell me what is the element of conducting a speed survey that - FOR PURPOSES OF DEMONSTRATING THE PREVAILING FREE-FLOW SPEEDS - requires a traffic engineer's expertise?

[themadnorwegian]

In section 627 of the California Vehicle Code, the legislature delegates authority to the Department of Transportation to determine the methods that should be used to conduct traffic surveys. The document that the DOT uses is called the California Manual on Uniform Traffic Control devices. This document, in its definitions section, specifically states that engineering studies must be either conducted or supervised by an engineer. The document defines engineer as a person registered as a professional engineer under Business and Professions Code 6706. See CA-MUTCD 1A.13 for the details.

Can you explain what you hope to accomplish here? VC 22354 and VC 22358 require that the DOT or a local authority initiate a survey when they want to reduce a speed limit on a state highway or local road, respectively. There's no provision for citizens to do this. Moreover, since you were cited for a 22350 where the police didn't use radar or laser, there's no requirement that the prosecution present an engineering survey. If you want to present one in court, you'll need to either hire a traffic engineer to testify on your behalf, or meet the requirements in the evidence code for expert witnesses. Evidence Code 720 says: "A person is qualified to testify as an expert if he has special knowledge, skill, experience, training, or education sufficient to qualify him as an expert on the subject to which his testimony relates. Against the objection of a party, such special knowledge, skill, experience, training, or education must be shown before the witness may testify as an expert." How do you plan to show that your training, knowledge, and experience qualifies you to offer an opinion comparable to one from a professional engineer?

[California student]

So, Huntington Beach sends police (i.e. non-engineers) out to collect the data which suggests that part doesn't require expertise. College-student agrees and says you need the expertise to "interpret" the data. Once the data is collected, it's just a bunch of speeds. the interpretation is finding the 85th percentile which is trivial.

Except that the 85th percentile isn't the only factor involved. Did the speed study also justify a 5 mph reduction? Also, what reason does the traffic engineer have to fudge numbers? Why should the court view your numbers with the same accuracy as from someone who isn't a party to the case?

[cdwjava]

The news article is nearly 18 years old. Maybe, once upon a time, they did it that way, but that hardly means that they are still doing it.

Also, if the officers are going out and collecting the data, it is likely that they are the ones setting up the equipment that collects the data, not that they are doing ANY of the calculations or interpretations necessary. Even if the officers collect the data, the engineer must still evaluate and certify the information.

In my county the traffic engineer does NOT go out and set up the equipment. He puts in a work order to county streets and THEY place the equipment per his instructions for the requisite period of time, and they remove it. The data is then provided to him ad he evaluates it and produces the report.

If you can get permission from the city to lay out your own survey equipment (which generally requires laying a line across a roadway and stapling it to the pavement) then, perhaps, you can get a decent survey. Otherwise, what do you plan to do? Stand there with a clipboard and estimate speeds? Buy and then run your own radar survey (which will be subject to a number of flaws)?

In any event, here is the law:

627. (a) "Engineering and traffic survey," as used in this code,
means a survey of highway and traffic conditions in accordance with
methods determined by the Department of Transportation for use by
state and local authorities.
(b) An engineering and traffic survey shall include, among other
requirements deemed necessary by the department, consideration of all
of the following:
(1) Prevailing speeds as determined by traffic engineering
measurements.
(2) Accident records.
(3) Highway, traffic, and roadside conditions not readily apparent
to the driver.
(c) When conducting an engineering and traffic survey, local
authorities, in addition to the factors set forth in paragraphs (1)
to (3), inclusive, of subdivision (b) may consider all of the
following:
(1) Residential density, if any of the following conditions exist
on the particular portion of highway and the property contiguous
thereto, other than a business district:
(A) Upon one side of the highway, within a distance of a quarter
of a mile, the contiguous property fronting thereon is occupied by 13
or more separate dwelling houses or business structures.
(B) Upon both sides of the highway, collectively, within a
distance of a quarter of a mile, the contiguous property fronting
thereon is occupied by 16 or more separate dwelling houses or
business structures.
(C) The portion of highway is longer than one-quarter of a mile
but has the ratio of separate dwelling houses or business structures
to the length of the highway described in either subparagraph (A) or
(B).
(2) Pedestrian and bicyclist safety.

And, a link to the DOT procedures:

http://www.dot.ca.gov/hq/traffops/si...TMChapter8.pdf

[California student]

I'm going to preface this by saying that I agree that this stunt isn't going to work and is a waste of time. However let me put on my devils advocate hat because I do see where the OP is going.

Can you explain what you hope to accomplish here? VC 22354 and VC 22358 require that the DOT or a local authority initiate a survey when they want to reduce a speed limit on a state highway or local road, respectively. There's no provision for citizens to do this. Moreover, since you were cited for a 22350 where the police didn't use radar or laser, there's no requirement that the prosecution present an engineering survey. If you want to present one in court, you'll need to either hire a traffic engineer to testify on your behalf, or meet the requirements in the evidence code for expert witnesses. Evidence Code 720 says: "A person is qualified to testify as an expert if he has special knowledge, skill, experience, training, or education sufficient to qualify him as an expert on the subject to which his testimony relates. Against the objection of a party, such special knowledge, skill, experience, training, or education must be shown before the witness may testify as an expert." How do you plan to show that your training, knowledge, and experience qualifies you to offer an opinion comparable to one from a professional engineer?

Assuming that the officer is going to testify that the OP was going an unsafe speed simply because he was going faster than the speed limit (unlike, say, weather or something else), if he can prove that the speed limit should be raised then there's a valid argument that he has met the second part of 22351(b). I don't think the defendant conducting his own speed study, even if the defendant was a licensed engineer, would meet the requirement of "competent evidence" simply because of the inherent conflict of interest. 22351(b) isn't reliant on how the speed was measured, just that it was a prima facie speed limit violation.

For the second part, if the judge is a neutral judge, and the officer is just a witness, then who is left to object to his testimony. I remember TG posting a link to case law that says that the judge can disregard expert testimony under certain circumstances, but at a minimum it gets presented (thereby wasting everyone's time).

[lbk]

Thank you "themadnorwegian"; your comments are critical but constructive.

I have a 22350 ticket. You correctly cite the MUTCD that a certified traffic engineer must conduct a traffic survey, and I am not a certified traffic engineer. The reason, as I understand the law, that a certified traffic engineer must conduct the survey is to ensure the survey has some validity if someone gets a ticket and challenges it under a speed trap law.

By contrast, I am not seeking to create a new 85th percentile for the city I was ticketed in. I am simply trying to demonstrate that I was driving safely under the conditions I was ticketed for. I define safe as 85 percentile or less for the conditions. I concede and agree wholeheartedly that my survey is irrelevant outside of my case. My survey provides competent evidence to overcome the prima facie case that my speed was inherently dangerous - or at least I'm willing to stand by it.

I concede also that "themadnorwegian" may be right in that a judge may not allow the evidence since I am not a certified engineer, but I'm not convinced at all yet. The Goulet case touches on this issue somewhat.

[themadnorwegian]

However let me put on my devils advocate hat because I do see where the OP is going.

I do like a good devil's advocate hat. Every time I put mine on, people think I'm after their women and cattle. I'll have to get one without horns, I'm afraid.

Assuming that the officer is going to testify that the OP was going an unsafe speed simply because he was going faster than the speed limit (unlike, say, weather or something else), if he can prove that the speed limit should be raised then there's a valid argument that he has met the second part of 22351(b). I don't think the defendant conducting his own speed study, even if the defendant was a licensed engineer, would meet the requirement of "competent evidence" simply because of the inherent conflict of interest. 22351(b) isn't reliant on how the speed was measured, just that it was a prima facie speed limit violation.

In this case, you're saying that the defendant is trying to attack the "established as authorized" part of 22351 (b)?

22351. (b) The speed of any vehicle upon a highway in excess of the prima facie speed limits in Section 22352 or established as authorized in this code is prima facie unlawful unless the defendant establishes by competent evidence that the speed in excess of said limits did not constitute a violation of the basic speed law at the time, place and under the conditions then existing.

I'll go with this just for the sake of argument, but I think it's an uphill battle for the OP. In particular, Evidence Code 500 places the burden of proof squarely on the defendant for this claim. In order to prevail, I believe the OP would have to show that speed limit was not a prima facie speed limit as per 22352; or that the city did not conduct an engineering survey before decreasing the speed limit on a highway; or that the speed limit was not lowered by ordinance; or that the survey did not find that the lowered speed limit facilitated the orderly movement of traffic in a safe and reasonable manner. To accomplish this, you'd need evidence not mere suggestion. For many of these, you'd actually need to be able to prove that the city failed to follow the rules. For last item, you probably need expert testimony.

By contrast, I am not seeking to create a new 85th percentile for the city I was ticketed in. I am simply trying to demonstrate that I was driving safely under the conditions I was ticketed for. I define safe as 85 percentile or less for the conditions. I concede and agree wholeheartedly that my survey is irrelevant outside of my case. My survey provides competent evidence to overcome the prima facie case that my speed was inherently dangerous - or at least I'm willing to stand by it.

I went back through the thread, but I can't find any information about what street you were cited on, what the posted speed limit was, or a copy of the city's survey. Would you post this information? It would make it a lot easier to discuss this in detail, instead of speculating about the theory of what you're trying to accomplish.

As to the question of competent evidence, unless you qualify as an expert witness you're probably not competent to present the survey. You'll need an alternative survey from an actual traffic engineer. If you're not a qualified expert, it's likely that the judge will rule that you're not qualified to offer an opinion about the the traffic conditions, beyond what a lay person is able to observe.

[lbk]

More excellent and constructive feedback, even though your conclusion is that my plan will fail.

I'll try to post a redacted copy, but I decline to include identifying information as a precaution. I could be excessively cautious here, but I ask for your consideration on that point.

In order to prevail, I believe the OP would have to show that speed limit was not a prima facie speed limit as per 22352; or that the city did not conduct an engineering survey before decreasing the speed limit on a highway; or that the speed limit was not lowered by ordinance; or that the survey did not find that the lowered speed limit facilitated the orderly movement of traffic in a safe and reasonable manner.

Close. I (perhaps mistakenly) assert that my survey provides competent evidence of a safe speed under 22351b. I consider this valid on its own without invalidating the prima facie speed limit (though I welcome your thoughtful commentary on this point). In addition, however, I intend to make a (less important) argument that the prima facie speed limit is invalid because it violates the requirements for a speed survey. In my view this argument, even if successful, likely only serves to shift the burden of proof to the prosecution which - at the point where I've already done a speed survey - is somewhat irrelevant. At any rate, I described all this in question #1 of the original post.

- - - Updated - - -

Slightly off-topic, but what I'm seeing is that cities post speed limits that they know are 2-7 mph (or more) below the "safe and prudent" 85th percentile. Evidently they do this for a combination of reasons including raising money (see the Goulet or Perez cases) or to cater to politics (I've seen retail groups advocate for slower speed limits so that customers will stop in their shops more). I'm sure safety is at least occasionally a factor, although surveys of traffic engineers have shown that politics is the major factor.

First off, it should be troubling that safety is not the key factor in setting speed limits.

Second, it strikes me that any traffic engineer must KNOW that it's always career-safe to choose the lower of two candidate speed limits, while it may be career-hampering to choose the higher of two candidate speed limits. Traffic engineers out there: have you ever faced political pressure to RAISE a speed limit?

[trafeng]

Anything is possible, but as a practicing traffic engineer who has had to go to court and defend such issues, my bet is that your plan will fail; not that that should discourage you from trying...

Your idea seems to be to show up to court with a study you have done on 85th percentile speeds and try to disprove the posted speed limit based on that. Your fixated on one aspect of speed limits to the exclusion of all others, and that is why you will fail in court. First, are you able to support that the location you gathered your speed data is more accurate than the location the municipality used? Would you be able to know the difference? What other factors might have been present when you or the jurisdiction collected data that might make one more preferable than another? What is your sample size? Did you deploy road tubes over 24 hours, 3 days, 1 week? I bet the agency did. Honestly, its unlikely the judge will even allow what you present as evidence. Anybody with a spreadsheet can develop lots of statistics, but that does not mean they are valid for the question at hand. How did you collect the data...? on and on the questions go; this one would be easy.

Now, onto the things your excluding; the other factors that should be included at a minimum:

Prevailing vehicle speeds (not just the 85th, but the 10mph pace speed)
Physical features of the roadway
Traffic control characteristics
Crash experience
Conditions not readily apparent to the driver

It sounds like you've got a copy of the MUTCD for your state, which includes other items. Safety is certainly a factor in setting speed limits, as is mobility, efficiency and traffic flow. From an ITE reference: "Use of the 85th percentile speed is based on the theory that the large majority of drivers are reasonable and prudent, do not want to have a crash, and desire to reach their destination in the shortest time possible."

Traffic engineers are under all kinds of pressure, but generally try to live by the data and explain it as best as possible. Just so you know, there are lots of requests to raise speed limits, not just lower them. Of note as well, the idea that cities generate large amounts of cash by sending officers out to write tickets is probably one of the greatest urban legends of all time; and so pervasive that most have just given up on trying to argue it. Automated enforcement (photo cop) is a completely different story however...

[lbk]

Thanks, trafeng.

Again, to be clear, I am not trying to REPLACE the city survey. I appreciate that many of you are pessimistic of my chances to have the evidence considered which is very helpful feedback to receive.

According to what's written on the city's survey, it was done for one hour (mid-morning): sample size just over 100.

The city cited as the reason for lowering the limit 5mph that they wanted to match the speed limit in the other direction. This strikes me as an invalid reason to lower a speed limit (creating an invalid prima facie speed limit), although ThatGuy suggests that the survey doesn't matter in California pacing cases.

I'm well aware of the other characteristics you cite, and to be brief, none justify a reduced speed limit (e.g crashes are 1/3 of the expected level).

I selected the location of my survey based on where I was ticketed (a very small area). Again, I'm not trying to replicate the existing survey, I'm trying to answer the question: what is the speed distribution and characteristics (85th percentile, pace, standard deviation, ...) for free-flowing traffic at the location and under conditions that I was ticketed for. The idea is to provide competent evidence to establish that I was driving safely.