What the heck is visual estimation? How police “guess” your speed

It’s literally a case of an officer giving his or her best guess on your vehicle’s speed. Frankly, we think it’s poor logic, but police are allowed to use a method called visual estimation to guess whether you’re speeding. Just like how it sounds, literally, all a police officer has to do is look at your vehicle and ask themselves whether you’re speeding. It doesn’t matter if you’re in the opposing lane or perpendicular to the officer’s vehicle – generally, the officer’s estimate of your speed will be upheld in court.

We don’t like it, and you shouldn’t either. After all, there’s a reason why officers’ speed estimates are often supported by radar or laser detectors. If a cop thinks you’re speeding, let them prove it by using a certified device to log actual evidence of the crime. Unfortunately, however, what an officer thought he or she saw is often good enough.

At the end of the day, police can guess your speed.

Why can police use visual estimation instead of equipment?

At the heart of the issue, it’s been established that the average person who is otherwise untrained is allowed to give descriptions of what they saw, and that these descriptions can be accepted by court. These descriptions might have to do with a person’s age, the distance one object is from another, whether an object is new, used, or worn, and indeed – how fast something is travelling.

It’s not too much of a stretch to suggest most motorists out there have a good idea of whether another vehicle is travelling unusually fast or slow. Often, the average person can even give a pretty good estimate of how fast something is travelling. Police are allowed to do the same, and in some cases are even afforded more credibility by the courts due to their status as police officers.

Police can even guess the speed of a vehicle in opposing lanes

This case went all the way to the BC Supreme Court. The driver was in the opposing lane and approaching a police officer on a rainy night. The officer testified that as the driver’s vehicle approached, he visually estimated a speed of “about 75 kph,” activated his emergency lights, and turned around to pull the driver over.

All that was written on the speeding ticket was that the driver was travelling over 50 km/h, the speed limit in question on that road. It’s important to note that this wasn’t a case where a police officer had followed a vehicle and gauged the leading vehicle’s speed using their own speedometer. The court even accepted that the only evidence that suggested the driver was speeding was one police officer’s opinion.

Nevertheless, the driver’s conviction was upheld. Here’s what the judge said:

“I am not persuaded that the fact that the two vehicles were moving toward each other in opposite directions adversely affected the officer’s opportunity or capacity to observe. It seems to me that (the officer) would have a good opportunity to estimate the speed of the appellant’s car as it got close to him and then passed by, immediately beside him. But even assuming there was some further disadvantage in this situation, there was a great difference between the officer’s 75 kph estimate of the speed of the appellant’s car, and the speed limit of 50 kph.”

Or they can guess your speed if you are travelling perpendicular to them

In this example from a driver in Burnaby, an officer again used a visual estimate to allege the driver was speeding. The officer in this case was stopped at a red light when he saw a vehicle travel approach the intersection “at a high rate of speed” in a group of cars. The officer was drawn to this particular driver since he felt the driver was the fastest of the group.

The officer believed the driver was travelling 90 km/h in a 60 km/h zone, and watched the vehicle pass the intersection as the light was changing. The officer gave chase, and testified that he had to speed faster than 100 km/h to catch up with the vehicle. He caught up about one kilometre away from the intersection.

The driver maintained he was travelling at the speed limit, but the court was satisfied that the driver was at least 1 km/h to 20 km/h above the speed limit. The court even acknowledged that the officer an an error rate of “plus or minus 10 kilometres an hour.”

Again, the court said the officer did not need to have forensic evidence to prove the speeding:

“The inference is that there should have been some forensic evidence to determine rates of speed and distances to prove (the officer’s) assertions that (the driver) was continuing to drive over the speed limit after the Intersection. However, it cannot be the case that simply because there was no other evidence on the point that the Judicial Justice was required to disregard (the officer’s) evidence on this issue.

Visual estimation is even easier if an officer is following you

And lastly, suffice it to say that if a police officer is following your vehicle prior to alleging that you’re over the speed limit, then it’s even easier for them to prove that you were speeding, since your speed is corroborated by the information from the officer’s speedometer.

At the end of the day, police can guess your speed. And you’ll be found guilty if they say you’re speeding, even if the only proof is some kind of “visual estimate.”

It might seem like the courts are relying on shaky evidence to prove the presence of a crime, but it’s well-established that an officer’s opinion can shape whether you walk away with a conviction or an acquittal.

However, there is more to defending speeding allegations than the ticketing officer’s opinion. As BC Driving Lawyers, our knowledge of the law has often proved to be the tipping point in challenging an officer’s allegations. We have been successful in challenging hundreds of speeding tickets, and do our best work particularly when the officer’s evidence is shaky. Dispute that ticket. Call us today. 604-608-1200.