The state has not proved its case against Duduzane Zuma, accused of culpable homicide after a car crash, his counsel argued.

'One wonders why a reasonable prosecuting authority would think there is reasonable prospect of success in this case,' Mike Hellens SC argued in the Randburg Magistrate's Court yesterday.

Zuma faces a charge of culpable homicide for the accident five years ago, to which he has pleaded not guilty, notes TimesLIVE.

Minibus taxi passenger Phumzile Dube died after Zuma's car crashed into a minibus taxi on the M1 south near the Grayston turnoff in Johannesburg in 2014.

Hellens argued that there was no evidence that Zuma was travelling at an excessive speed when he overtook the minibus taxi. Hellens contended that Zuma could not avoid aquaplaning (losing control of the vehicle because of water on the surface of the road).

'What could Mr Zuma have done to avoid aquaplaning that night? At what speed was he supposed to drive that night to avoid aquaplaning? There was a puddle of water and a reasonable driver would not have foreseen it,' Hellens said.

According to Hellens, when a car aquaplanes, anything can happen, including it spinning.

Prosecutor Yusuf Baba argued that aquaplaning did not happen on its own and that there were factors affecting it such as 'tyre pressure, the speed of the vehicle'.

Baba said it was up to the court to rule on whether Zuma had been driving negligently.

'The court has to determine the following: did Mr Zuma drive the car as a prudent driver, did he take precautions and did he reduce his speed?'

'He failed dismally,' Baba argued.

The case was postponed to 12 July for judgment.

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