The decision on whether a protest is deemed unlawful hinges on whether it causes “serious disruption”.
This assessment is made by a number of organisations including the Metropolitan Police, the local council, Transport for London and the emergency services.
In October, this decision was taken almost as soon as a protester sat down to block a street, but the moving barricade appears to be buying the group more time.
Pedestrians began shouting at police for not arresting members of the group.
Questioned by a pedestrian as to why he was not arresting protesters, a third police officer said: “They’re not blocking the highway – they’re moving. If this group stop, that’s a different thing but they’re moving.”
A fourth police officer told The Telegraph: “By moving you’re just on a protest, on a March, effectively. Unless they stop, they’re not breaking the law. The problem is the traffic can get past when the opportunity arises – it’s a proper grey area.”
A Met Police spokesman said: “Everybody has a right to protest, but they do not have a right to commit crime whilst doing so, or to disproportionately impact others.
“We are alert to the new Just Stop Oil tactics and will move quickly to intervene where serious disruption is being caused.
“There was a small amount of disruption to already very slow moving traffic. No arrests were made.
“We will continue to monitor this closely and develop our response to effectively balance people rights and keep London moving.”
According to the legislation, obstructing the highway happens if a person, without lawful authority or excuse, in any way wilfully obstructs the free passage along a highway.
A constable may arrest without warrant any person whom he sees committing an offence against this section, the law states.
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