Civil disobedience is the duty of everyone.
What about slow driving? Cars are bigger anyway and if you for example need some time to slowly cross a red light one car per phase, it completly crashes the cities transport system. For a city like London that would work perfectly.
That reminds me of when the 'freedom' convoy took their protest to a large city, and their protest ended up being just normal bad traffic. Obligatory Good Omens M25 YT scene.
I imagine any reasonable traffic law would forbid drivers from impeding traffic like that. You might be able to do it somewhat discreetly, but it's still a matter of enforcement, and you can bet blue nonces will suddenly start caring about enforcing traffic laws.
Edit: UK Road Traffic Act
If a person drives a mechanically propelled vehicle on a road or other public place without due care and attention, or without reasonable consideration for other persons using the road or place, he is guilty of an offence.
Kinda defeats the point of a climate protest if you're idling in a car.
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