The Singapore Democratic Party's (SDP) application to have its court challenge against the fake news law heard in open court was unsuccessful because there was "no special reason" to do so, said Deputy Attorney-General Hri Kumar Nair.

Speaking to reporters outside the courtroom yesterday, Mr Nair said public interest - which the SDP cited - was not enough of a reason for a given case to be moved from chambers and made open to the public.

He added that many past cases - even those involving constitutional changes - have not been deemed "special enough" to meet the legal threshold.

The High Court said on Tuesday that all cases brought by originating summons (OS), one of two ways of initiating a civil action, are heard in chambers, according to court rules.

The Protection from Online Falsehoods and Manipulation Act (Pofma) rules provide that all High Court challenges against Pofma corrections must be filed by OS. This means that, by default, all Pofma cases will be heard in chambers unless there is a legal reason for it to be heard in an open court.

Veteran lawyer Amolat Singh said that in an OS case, all pertinent facts, arguments and pieces of evidence are submitted on paper, and a judge will typically issue a decision based on these documents.

This means a case filed by OS can be concluded much more quickly compared with a writ action, which can involve the cross-examination of witnesses and other procedures.

Mr Singh said an OS case can be concluded in four to six weeks, while a writ action can take six to nine months. This is the main reason Pofma cases are to be filed by OS, he added.

One "special reason" for converting an OS into a writ action, thereby moving it to an open court, is if there is a "substantial dispute of fact" in the case, he noted. A judge may then decide that it is necessary to cross-examine both parties to a case and assess their credibility.

In the SDP's case, the underlying facts are not in dispute, said Mr Nair.

"Both parties are relying on the same MOM statistics and no one is saying those statistics are wrong."

Mr Nair also said the law provides for a list of originating summonses which will be heard in open court, and Pofma cases do not fall within that list. The list includes applications under various laws such as the Companies Act and the Patents Act which set out specific conditions.