Mr Justice Higgins refused to announce his judgment after police struggled to keep rival loyalist factions apart outside his courtroom.
A number of people were injured and at one stage a threat was made to throw one man over a fourth-floor balcony. After the violence, the judge said he was deferring the case of a brother and sister accused of involvement in the murder of millionaire loyalist drugs baron Jim Johnston.
Judge Higgins announced his decision to delay the verdict 90 minutes after the brawl involving up to 25 people, mostly men, erupted on the top floor of the building at Laganside Courthouse. Extra police rushed from the neighbouring High Court building as well as two on bicycles who had been on city centre duty.
The men, most of whom attempted to conceal their identity with baseball caps, zipped up jackets and hooded tops, were escorted from the building.
As they left the court some of them chanted support for the Loyalist Volunteer Force, bitter rivals of the Red Hand Commando which is linked to the Ulster Volunteer Force. There were no arrests.
Mr Johnston, 45, a member of the RHC, was shot outside his home in Crawfordsburn, Co Down, on the eastern outskirts of Belfast in May 2003.
Robert Young, 41, from Ulsterville Park in Portadown, Co Armagh, denied murdering Mr Johnston. His sister Lorraine, 39, from Holywood, Co Down pleaded not guilty to providing him with a false alibi. A second woman,
Susan Ferguson, 36, also from Holywood, denied three counts of possessing firearms. Young was remanded in custody but the women were granted bail.
When the court reconvened after the fighting, Judge Higgins said: “I am deferring giving judgment on this case today.
“The parties will be informed when the case will next sit.”