Police breached the rights of campaigners by stopping them from attending a mass rally against the Iraq war, a judge has ruled.
Up to 159 protesters left London on coaches to attend the demonstration at RAF Fairford in Gloucestershire two days after the coalition forces launched their assault from the airbase in March 2003.
But they were stopped at Lechlade, a few miles short of the airfield, and sent back to the capital under police escort.
Judge David Mitchell, sitting at Central London County Court, ruled that Gloucestershire Police breached protesters' rights to freedom of expression and freedom of peaceful assembly after hearing 12 test cases brought by campaigners.
In his 87-page ruling, the judge said the claimants' main concern was that they were unable to take part in the protest.
But he also agreed that they had to endure "humiliating circumstances" by being forced to travel back to London without being able to use the toilet.
The men and women were not allowed to use a motorway service station, with many forced to use plastic containers to relieve themselves on board the coaches.
Many also went hungry and thirsty, while others said they felt intimidated by the heavy-handedness of police, who the judge said behaved in an "oppressive manner".
By stopping the group from going to Fairfield, officers demonstrated "an interference with the right of ordinary citizens to go about their business", he added.
Describing the anti-war protesters, he said: "The vast majority of them - as this case has proved - were decent, hard-working people who had never been in trouble with the police. Surely the police officers on the ground must have realised that they were not dealing with coaches packed with hardline anarchists."