In the days when the Motorcycle Action Group did stuff like that they briefed everyone to insist on a full trial.
Nobody even made it to the steps of the court...
The authorities backed down every time when confronted with only a couple of hundred people prepared to go to trial by jury.
When confronted with a couple of thousand they didn't even threaten.
The court systems has a massive backlog without several hundred angry people making political points by representing themselves.
The first thing you do is put the Minister of Transport and the local Chief Constable on your witness list.
It gets thrown out of course, but they have to have a pre trial hearing do to that, and that's two days.
Political trials are a nightmare and the government knows this and just doesn't want any.
Just about the only ones that happen these days are fascists getting dragged through the courts for 'incitement to racial hatred'.
There's one going on at the moment for some slimeball called Sheppard (he's so extreme the BNP threw him out for being too nasty) and so far the pre trial hearings have lasted for almost two years.