Finance Minister Pravin Gordhan had instituted the inquiry following media reports about a telephone conversation during which Oupa Magashula was recorded offering a woman Chartered Accountant a job at SARS in contravention of the institution's policies.
"The conversation was facilitated by a Mr Timothy Marimuthu, whom media reports alleged had influence over Mr Magashula. The effect of these reports was to raise questions about the integrity of staff recruitment processes at SARS," Gordhan said.
But the inquiry also reported that the allegations of Marimuthu's influence over Magashula could not be probed because Marimuthu "did not respond positively to the request for an interview".
"The committee was unable to pronounce on the precise number of people who may have been involved in what the committee sees as the attempt to blackmail the SARS Commissioner," Gordhan said.
The probe was initiated after the weekly City Press reported details of a clandestine tape recording laced with sexual innuendo in which Magashula and Marimuthu offered a lucrative SARS post to a woman known to Marimuthu.