Judgment was reserved in Cape Town Mayor Patricia De Lille's court bid to have a motion of no confidence in her held by secret ballot.

"This court's ruling will stand over until tomorrow until 2 o'clock," said Western Cape High Court Judge Robert Henney.

De Lille brought the urgent application so that Thursday's motion of no confidence in her, set for 10:00 at the City of Cape Town's council meeting, be one of "conscience" and "free will", instead of DA councillors simply doing what their party tells them what to do.

She also wants the vote to be held in secret so that none of the councillors fear any reprisals by party officials who see how they vote.

Currently they vote by raised hand, or electronically.

It is in the Speaker's discretion to say whether it can be a secret vote or not, if the issue arises, according to council rules.

De Lille brought in advocate Dali Mpofu to argue her case because he had handled the United Democratic Movement's similar application to the Constitutional Court to force Speaker of the National Assembly Baleka Mbete to hold a motion of no confidence in President Jacob Zuma in secret.

This was to allow ANC members to vote as they pleased.

In that case, the court ruled that it could not tell the speaker to hold the motion of no confidence in secret, but said she had the authority to decide whether to hold a secret vote or not. Mbete went ahead with the secret ballot and Zuma survived.

The DA is in the majority in the City of Town, and De Lille is serving her second term as mayor, on a DA ticket. But the federal executive, chaired by James Selfe, wants her out and told its caucus in council to vote her out via the motion of no confidence.

It has since done an about-turn, and said its members in council can vote freely, with no fear of reprisal. But De Lille insists this is not enough and that a secret vote is required.

She has also been taken off communication related to the City's Day Zero water scarcity crisis, with Democratic Alliance leader Mmusi Maimane controversially holding a press conference to communicate the City's efforts.

De Lille has been accused of allegedly covering up claims of corruption in the transport department. The party also helped entrepreneur Anthony Faul lay a criminal case against her for allegedly trying to solicit a R5-million bribe, more than 5 years ago, for the supply of fire extinguishers to Imizamo Yethu.

She has denied the claims.

On Friday, the DA gave De Lille until 15:00 to withdraw her application, stating that she did not understand the law, but De Lille went ahead. She believes the motion of no confidence is a bid to remove her without having to go through disciplinary proceedings.

In the lengthy argument in court, Henney repeatedly wrestled with whether he had the right to tell a party or a council what to do regarding a vote.