THERE were no juggling acts or balloon animals but the clown suit was almost enough to land a man in jail when he represented himself in a Sydney court.

Shane Cuthbert, 22, was nearly slapped with a contempt charge, in the name of preventing anarchy, when he appeared in a clown suit in Parramatta Local Court on Wednesday.

The landscaper from Blacktown said he'd earlier been warned by a court officer to take off his rainbow wig before representing himself on a count of damaging the side mirror of a taxi.

But the clown suit was enough for magistrate Anthony Marsden to threaten him with jail.

"Why are you dressed as a clown?" Mr Marsden asked.

Mr Cuthbert said he was protesting religious extremism and the use of children in such behaviour, but the magistrate said a court was not the forum to raise awareness of any particular issue.

"I'm seriously considering holding you in contempt of court," Mr Marsden said.

"You have rights and you have freedoms but they are not unlimited, otherwise, there would be anarchy."

Mr Cuthbert, after saying he meant no disrespect, was let off with a warning to dress appropriately at his next court appearance.

He pleaded not guilty to the charge of damaging the taxi mirror and will appear in the same court on November 7.