Judge Siraj Desai ruled on Wednesday that the defence may not put up its technical experts before Henri Van Breda.
The judge said there was possible prejudice and Van Breda could modify or amplify his version.
Hendri van Breda's defence Advocate Botha then said for the moment the 22-year-old murder accused would not testify.
Van Breda is accused of the murder of his parents and older brother and the attempted murder of his younger sister in their De Zalze Estate home in Stellenbosch in 2015.
Kelly Phelps, a public law lecturer at UCT chats to John Maytham about the latest events.
As a general statement, a judge won't draw any negative inference from an accused choosing not to testify. And the reason for that is it strikes right at the core of the rights to a fair trial....All accused persons have a right to remain silent.— Kelly Phelps, a public law lecturer at UCT
But that doesn't apply equally in all cases, she says.
In some cases, the defence will rely heavily on what the accused was thinking at the time - their subjective beliefs at the time.— Kelly Phelps, a public law lecturer at UCT
And in such instances, if the accused refuses to testify willingly, the court may be forced to draw inferences for want of any other evidence, explains Phelps.
She says court is a difficult environment and sometimes it is not a good idea for the accused to testify.
Take a listen below to Phelp's argument: