British Law Lords have ruled that participants in Critical Mass cycle rides in London do not have to give police advance notification of the route of their rides.

Police had demanded that they be notified of the time, date and route of any Critical Mass ride in the capital, but cyclists argued that they could not provide details as no one is in charge of the rides, nor is there a planned route. The concern was that police could use advance information to effectively ban the ride.

The ruling comes as a result of an appeal by cyclist Desmond Kay, who appealed against the Court of Appeal’s ruling that the Metropolitan Police should be given advance details of the ride.

“This was a very important case for people like me who have cycled with Critical Mass for many years,” Kay said after the ruling. “More importantly, I hope that it will encourage other cyclists to join the monthly rides.”

The case – rather like a Critical Mass ride – has taken a twisting an unforeseen path through the British legal system over the past three years. Back in 2005, Kay, backed by Friends of the Earth, launched a successful High Court challenge to the police’s argument that Critical Mass is a demonstration. Kay argued “that the monthly rides are lawful because they fall within an exception for processions that are ‘commonly and customarily held’.”

The High Court agreed but then the ruling was over-turned at the Court of Appeal. Now that decision, too, has been reversed.

Critical Mass rides take place in central London during the evening on the last Friday of every month. Riders assemble at the South Bank at 6pm.