Willie Frazer has claimed his arrest over loyalist flag protests was an attempt to silence him after charges against him were dropped by the Crown.
Speaking outside Belfast Magistrates Court, the Protestant victims campaigner demanded that the police officer in charge of the case against him be held publicly accountable.
Prosecutors told the court that there was insufficient evidence over allegations that he took part in an unnotified public procession and encouraged others to do the same by making a speech at City Hall.
"It is perhaps the first time in a long time that justice has been done in this country," Mr Frazer said.
He said he believed the charges were "nothing more than an attempt to silence me".
"I will be rigorously pursuing this matter via the Police Ombudsman," he added.
The development leaves Frazer facing a single count of possessing a stun gun.
The 53-year-old from Markethill, Co Armagh, was one of the most high-profile figures brought before the courts amid demonstrations over a council decision to limit the flying of the Union flag at Belfast City Hall. He was accused of encouraging or assisting offences by a public address, and taking part in unlawful marches.
But with other charges having already been withdrawn, District Judge Fiona Bagnall was told two remaining counts connected to a protest on January 19, 2013 were being dropped.
With the flag-related charges abandoned, Judge Bagnall agreed to lift a ban on Mr Frazer participating in any public demonstration.
A ban on going within one mile of any protest or procession was also removed.
A contested hearing on the remaining charge of Mr Frazer having a stun gun is due to go ahead next week.
"There have been disclosure issues over the last number of months and the prosecution have been coming into possession of bits and pieces of information.
We have now stood back, reviewed the case, and the evidential test is no longer viewed as being met in respect of (the two charges)."
Public Prosecution Service lawyer John O'Neill