Mandla Manzini, for Edwin Cruywagen, argued that the witnesses in the attempted murder case against his client had scores to settle, a Sapa correspondent reported.
Cruywagen, who has pleaded not guilty to attempted murder, is accused of hitting his wife, Francis, with a hammer at their Hazyview home in June 2011.
The court heard that the wife suffered brain damage from the attack and that her family took her to the United States, where she later died.
However, the State was unable to charge him with murder because they could not contact the wife's family since her death.
The court heard that Cruywagen's former employee George Mohlala and his friend John Patrick Herbst testified that the accused admitted to them that he had killed his wife.
But his lawyer said the former employees were not reliable witnesses.
Magistrate Shelly Khumalo postponed the case to 7 April for judgment.