This section is only worth reading if you’ve had a run-in with a dangerous driver. Otherwise, feel free to skip it

Handbrake interface: use to prepare your evidential video clip for Police

Another way we can reduce risk to cyclists is by bringing aggressive, dangerous motorists to the attention of the Police. Note the key words “aggressive” and “dangerous“. Motorists will make technical driving errors; happens to all of us at one time or another. The key question to be answered before escalating your helmet camera footage to the Police is:

Is it a matter of ‘WHEN‘ this motorist strikes a cyclist rather than ‘if’?” If it’s an honest “yes”, then it’s worth escalating to the Police. Drivers with points on their license have to be hyper vigilant they don’t exceed 12 points, so they’ll have to behave themselves, especially if they drive for a living.

However do NOT be petty and use helmet camera footage to avenge a technical driving error; we all make them. Banging other road users for an inadvertent driving error is being a dick. Do not be a dick. It gives cyclists a bad reputation as malicious road users.

If the incident is serious enough, I’ve documented a procedure which I followed to successfully enforce a driver by the Police when an aggressive driver nearly killed me.

Do you have a Plate Number?:

1. Does the video capture the plate clearly? If you not, don’t bother pursuing the matter with the Police; you’d be wasting both their time and your own.

Are you within time?

2. The Police are legally obliged to send their notice of intent to prosecute within (I believe) ten days. IF you wait too long, the Police will not consider your evidence, no matter how good it is.

Objectively Determine Severity:

Really the litmus test in seeking to have a motorist enforced by the Police is whether you believe that sooner or later they’ll manage to kill a cyclist- or pedestrian. Cyclists should be fairly circumspect in enforcing motorists with helmet camera footage. If they can answer “yes” without hesitation to both the following questions, then the camera footage is probably fair to submit to the Police:

3. “Was the act sufficiently outrageous that it could NOT be explained as a product of driver error?“: We all make technical errors; humans are not infallible. I’ve been struck by an elderly motorist driving a Jeep SUV while riding my PF. It was an accident, not the product of aggressive driving. However, the driver I had enforced by the Police had to first ignore my hand signals to almost kill me; he did it with eye’s wide open. On a 50” Penny-Farthing, it was IMPOSSIBLE for them not to see me signal. So they met the first test by virtue of wilfully disregarding my hand signals which excluded the potential that a confusion about my intentions could be operative and the VIDEO evidences outrageousness beyond a doubt.

4. “Was the act intentional?“: Generally, intent to commit an offense matters when pursuing an offender. Objectively distinguish driving error from malicious intent. Using the example of the elderly motorist,  I knew he made an error: he stopped, profusely apologized and offered to pay for the damages he caused. So neither was there intent to strike me. I has 100% confidence this motorist will be looking for cyclists in the future and didn’t require enforcing. Yes, he could have killed me, but he didn’t.  I just felt given his true contrition and honesty that he was worthy of forgiveness. However, the driver I DID have enforced was NOT.  Their driving was absolutely outrageous, the product of aggressive driving and no mere technical operator error. I had every belief they would eventually kill a cyclist or a pedestrian and escalation was the most appropriate form of resolution.

The expression “When you have a hammer, everything looks like a nail” comes to mind when enforcing motorists. Some cyclists look to foment confrontation with motorists to get close-pass material for YouTube.  Don’t be an asshole- escalate to the Police to improve safety, not to revenge an unintended technical driving error by a motorist.

The Process:

I’ll detail the process for how I pursued the enforcement of an aggressive driver here in the UK with the Hertfordshire Police.  Obviously the process will vary according to jurisdiction. Standards are disjointed on Police using cycle-cam footage. However, in at least (3) counties- Bedfordshire, Cambridgeshire & Hertfordshire– there is a single unified reporting process. So the same link that I used and provide herein works for two other counties.

5. Be able to articulate the details of the incident in relation to a law the motorist has broken: Being “offended” or angry by bad driving is simply not enough. The Police will require a narrative that details some infraction of a traffic law. To asses the dangerous act against Road traffic offenses, visit:

If you’re satisfied that the video evidences some offense under the law- and you’re willing to attend Court if the motorist denies their guilt- you’re NEARLY ready to pursue the incident with the Police. If you’re NOT prepared to attend Court, they why should the Police pursue the matter?

6. WARNING: Your own actions as a road user will be equally scrutinized as the motorist’s: The Police will quite rightly want to review the cyclist’s video footage in the context of the events surrounding the incident. They want a minute of video both BEFORE and AFTER the incident. They need to satisfy themselves that you didn’t play any part in escalating the incident to dangerous proportions. If a cyclist can’t provide a video clip with this before & after video context, or if they do and it shows the CYCLIST blowing through red lights and committing other Highway Code infractions- they won’t be impressed and might additionally enforce YOU. Also be aware that Police in Wales have disallowed helmet camera evidence of cyclists swearing like a drunken sailor after being triggered by a dangerous motorist.

7. Publishing the video online-WAIT!: If the Police decide that the incident is not enforceable, you’re wide-open to being pursued by the motorist if you’ve torn them up in a big public forum. There is value in posting close-pass or other dangerous driving video footage to educate both motorists & cyclists. However, there’s no upside to posting video for merely revenge purposes and makes the cyclist look as bad- or worse- then the motorist they’re trying to publicly tar-and-feather. Resist the temptation to engage in public shaming for the sake of public shaming.

Preparing the Video Evidence:

8. Preparing the Videoclip: NEVER work on the ORIGINAL- always operate on a COPY! Once the original has been modified, the Police won’t bother with it. My GoPro creates 4GB video clips with about 8 minutes video recording at 4K; the Police don’t want all this. create a copy of the folder with the video evidence and use the FREE opensource program Handbrake- – on a COPY of the clip. You open the copy in Handbrake and specify the length as a duration from the beginning to the end. 

EXAMPLE: If a close-pass happened at 3 minutes into your helmet camera video and the Police want a minute before and after, then the FIRST number would be 120 seconds and the SECOND number would be 240 seconds. See graphic at top of this page for the annotated Handbrake interface.

Submitting the Video:

9. Address to report camera video for Hertfordshire. Please note that Cambridgeshire & Bedfordshire run this service jointly with Herts Police:

You’ll first be asked to describe the incident and then be sent a link where you can submit the video and/or pictures.

If the Police concur the driving was a standard that should attract enforcement, they will email you their decision:

Dear Sir / Madam

Thank you for the submission of your footage, we have now reviewed the footage and will be taking the most appropriate positive action, in relation to the incident you have reported.

These options include the following:

*Warning letter

*Course offer

*Points and fine


Due to the Data Protection Act 2018 we are unable to provide you with the exact outcome or action that your submission has generated. Further information about the Data Protection Act can be found at

Yours Sincerely

Digital Evidence Team