Jacob Zuma must take the witness stand in his rape trial or face the consequences. This is the clear warning after the dismissal of his application to have the case against him thrown out.

Mr Justice Willem van der Merwe, ruling on a mid-trial defence bid to have the rape case dismissed due to lack of persuasive evidence, said yesterday the trial would continue because the charges could yet be proven.

"The accused is therefore not entitled to a discharge," Judge Van der Merwe told a packed Johannesburg High Court.

He disagreed that the evidence led by the State had been so poor that it should not be accepted. He believed that mens rea (criminal intent) could be found to exist even if no further evidence was led.

"I am of the opinion that there is evidence before me that if nothing more is said, a finding of mens rea to rape can be made," he said.

In South African law, in order to convict a person of rape, the prosecution has to prove two things: first, that an illegal act was committed; and secondly that the perpetrator had the intention to commit such an act.

Citing a number of legal precedents, Judge Van der Merwe asked: "With the foregoing in mind, the question in the present matter then remains ... is there evidence on which the accused in this matter might reasonably be convicted?

"Put differently, is there a possibility of a conviction even if he does not enter the witness box and then incriminate himself?

"Put even more simply: will the accused be convicted at the end of the case if he closes his case without testifying or without leading evidence?"

The judge was suggesting that it was necessary for Zuma to take the stand in his own defence, as well as responding to a request by Kemp that the court clarify its stance on the State's prospects of success.

Kemp had applied for the discharge under section 174 of the Criminal Procedure Act. He argued that the State had not proven beyond a reasonable doubt that Zuma raped a 31-year-old HIV-positive family friend at his Johannesburg home.

Kemp called the woman an accomplished liar and told the court there was no medical evidence of rape.

He pointed out that the defence had never suggested that the complainant had been a "plant" in Zuma's home. But it was odd that, in the days following her alleged rape, she had cellphone conversations with her mother and with Intelligence Minister Ronnie Kasrils.

Kemp had also asked that the evidence of two police officers, Superintendent Peter Linda and Commissioner Norman Taioe, be found inadmissible because they had not read Zuma his rights on one occasion, had not filled in certain vital forms and had apparently tried to "trap" him.

But Judge Van der Merwe said he would make a ruling on their testimony only at the end of the trial.

Asked if his client would take the stand first when the trial resumes on Monday, Kemp would not give a direct answer.

He would also not say which defence witnesses he would call.

The case continues today.

With acknowledgement to Jeremy Gordin and Cape Argus.