Vusi Mona said he believed he was perfectly entitled to run the story, taking into account supporting documents shown to him and his discussions with other journalists.
When told under cross-examination that it was a reckless decision, Mona reacted that it was for the courts to decide whether it was reckless or defamatory.
Mona was ultimately responsible for the decision to run the September City Press report in which the allegations against the national Director of Public Prosecutions first surfaced.
It asked the question whether Ngcuka was an agent of the apartheid government.
The City Press published the story after Mona's former rival editor, Mathatha Tshedu of the Sunday Times, had refused to do so.
Advocate Norman Arendse, counsel for Justice Minister Penuell Maduna, grilled Mona yesterday over his decision to disclose details of an earlier off-the-record briefing with Ngcuka.
Mona officially complained at the beginning of October to the Public Protector about the meeting that was held in July with a selected group of black editors.
Mona was among them.
The Public Protector has since referred the matter to the Hefer Commission.
Arendse accused Mona yesterday of violating a sacrosanct journalistic convention to never disclose details of off-the-record briefings without consent of the people who hosted it.
Mona argued that it was his citizen's duty because Ngcuka illegally disclosed at the meeting confidential information about people investigated by his Scorpions unit.
"I am a citizen first, and then a journalist," Mona declared.
He denied that he was prompted to go public by Ngcuka's announcement that a prima facie corruption case had been established against Deputy President Jacob Zuma.
Mona further denied that reported allegations against himself led to his official complaint against Ngcuka. The Star revealed at around the same time that Mona was allegedly involved in a communications company with a Mpumalanga government contract.
Shortly afterwards, Mona stepped aside from his editorial position and consequently resigned.
Mona said yesterday he did not expect the allegations against himself to be part of the Hefer proceedings.
His cross-examination continued yesterday afternoon. – Sapa.