The Freedom of Expression Institute has warned that the "bully" tactics employed by the police and the National Prosecuting Authority during the court appearance of Jacob Zuma could set the tone for his trial.

Jane Duncan, the executive director of the institute, said: "These events bode ill for the media's ability to cover the trial as it unfolds, and sound warning bells that attempts may be made by Zuma's team to hold the trial in camera."

Duncan has also sharply criticised the way in which policemen and Zuma's bodyguards prevented the media's access to the court.

"The police simply do not have to power to limit what is effectively a constitutional right of the public to a transparent judicial system. This can only be done on very limited grounds, and the magistrate should do so only once an application for an in camera hearing has been made.

"In the absence of such a process, the actions of the police are arbitrary, censorious and partisan," said Duncan.

Although no application had been made to hold the matter in camera, police area commissioner Oswald Reddy told journalists that the proceedings were "confidential", and Zuma's bodyguards physically prevented journalists from entering the courtroom.

"By declaring the proceedings confidential, and then responding in a very mocking manner when challenged by the journalists, he... demonstrated a contempt for media freedom in general," Duncan said.

She added it was also unacceptable for the police to allow Zuma's bodyguards to manhandle The Star's photographers.

"Their actions also smack of collusion between the police and the area commissioner with Zuma's team to shield him from further public embarrassment, which is an unacceptable form of bias... The police gave the impression that they were merely an extension of Zuma's bodyguards," Duncan said.

Yusuf Abramjee, the head of news and talk programming at the Primedia Broadcasting Group, said barring the media from the courtroom was "totally unacceptable".

"We are considering launching a formal complain with the Public Protector.

"Justice needs to be transparent, and by having secret court appearances, we are depriving the public of the right to information... "It is unacceptable that a veil of secrecy has been thrown over this particular case. All suspected criminals should be treated alike," Abramjee said.

National Prosecuting Authority spokesperson Makhosini Nkosi said Zuma was not given any special treatment.

Asked why journalists were not allowed into the court, Nkosi said: "The NPA does not control courts - it's the responsibility of the Department of Justice, while security at court is the domain of the SAPS."

Neither Justice Ministry spokesperson Leslie Mashokwe nor Gauteng Police Commissioner Perumal Naidoo could be reached for comment.

With acknowledgements to Penny Sukhraj and The Star.