A South African digital forensic expert on Friday denied allegations that he interfered with or altered data extracted from the cellphone of businessman Vusimuzi “Cat” Matlala and his wife, Tsakani Matlala.
Ratlhogo Peter Calvin Rafadi rejected the claims during cross-examination at the 57th session of a trial in Juba, describing the accusations as “unfounded and baseless.”
Allegations surfaced in October 2015 suggesting that Rafadi had tampered with cellphone data belonging to the Matlalas. The claims arose during investigations linked to politically motivated killings in South Africa, where the integrity of digital evidence has been scrutinized by witnesses.
A witness identified as Witness C from the Political Killings Task Team testified that data from the Matlalas’ previous devices could not be downloaded because of technical failures, raising suspicions of possible tampering.
According to the testimony, the witness suggested Rafadi may have altered the data in a way that compromised the investigation and undermined public confidence in efforts to address political violence.
During questioning in Juba by Machar’s defense lawyer Dr. Geri Raimondo Legge, Rafadi was asked whether there had been any breaches, complaints or incidents that could affect the integrity of his laboratory work.
Rafadi denied the accusations, saying the claims were based on speculation.
“There are unfounded allegations suggesting that I could have tampered with the phone of the suspect so that it could not be downloaded,” he told the court.
He said Witness C had testified that he had the expertise to block access to the phones but nonetheless concluded that Rafadi might have interfered with the devices.
“I wish to repeat these are unfounded allegations. As a seasoned digital forensic expert, I have worked closely with law enforcement,” Rafadi said, adding that his professional record includes appraisal letters from police units.
Rafadi, who owns a private forensic investigation firm, said the phones in question were never brought to his laboratory and were never in his possession.
He also said technical difficulties can arise when investigators who are not properly trained in digital forensics attempt to access devices using incorrect tools.
Presiding judge James Alala Deng adjourned the trial until Monday, March 9, to continue Rafadi’s cross-examination.
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