A potential juror attracted the wrath of a judge after he noticed the "fcuk" logo used by French Connection UK on the man's T-shirt.
Judge Huw Daniel, sitting at Mold Crown Court, said the T-shirt's "mis-spelt Anglo Saxon word" was a distraction and did not dignify the court proceedings.
Judge Daniel had looked up when the man failed to properly take the oath and he noticed the offending T-shirt.
The man was then asked to stand down and another juror was sworn in.
Court officials explained to the man in a side room why he had been asked to leave.
The man, who has not been named, later left the court.
"I don't want to say anything. I am self-employed and I am going back to work," he said.
The mis-spelling of a basic Anglo Saxon word on a garment hardly dignifies the court proceedings
The T-shirt was covered up by a coat as he left the building.
While the jury was out of the court, Judge Daniels explained to both legal teams his reasons for asking the man to leave.
"I stood one of the jurors down. He didn't take the oath properly.
"Secondly, the mode of dress was a potential source of distraction.
"The mis-spelling of a basic Anglo Saxon word on a garment hardly dignifies the court proceedings," he said.
"It is beyond me why anyone can think that they should wear anything like that in public, particularly in court."
Following the "fcuk" logo launch in 1997, French Connection UK reported a sharp rise in profits.
But the lettering has attracted criticism, including a ruling two years ago by the Advertising Standards Authority, which ordered the firm to pre-submit future poster campaigns for vetting.
In 1999, when the fashion house mounted a legal challenge to stop another company using the logo as an internet address, High Court judge Mr Justice Rattee branded it "obnoxious".
In a previous case at Mold Crown Court, officials offered a cardigan to a young woman who turned up in a revealing top.
The adjacent magistrates' court has a rule of not admitting anyone wearing shorts.