Kim Dotcom says he considered hiring a private investigator after WhaleOil blogger Cameron Slater repeatedly posted "smear stories" about him, but denies hacking Slater's computer.
Slater's hacked correspondence was released to investigative journalist Nicky Hager, who published it in his book, Dirty Politics.
Emails and Facebook communications have since been released online by someone claiming to be the hacker, who uses the Twitter account @WhaleDump.
Dotcom said on Radio New Zealand's Morning Report programme he was not behind WhaleDump either.
He had considered hiring a private investigator to monitor Slater, but changed his mind when he considered how he had felt being monitored by the Government Communications Security Bureau (GCSB).
Dotcom had been preparing to bring legal action against Slater for more than three months. He had had lawyers monitor the WhaleOil website daily to build the case.
Dotcom spoke at the Internet-Mana Party launch yesterday of using his hacking skills when he was 19 to alter the credit rating of German chancellor Helmut Kohl to zero because he "didn't like the guy".
"And you have all figured by now that there's another prime minister I don't like," Dotcom said.
Party press secretary Pam Corkery swore at journalists yesterday when they wanted to interview Dotcom after the launch.
"We've talked about jobs today and people living in poverty - you want to interview Kim, who said no interviews, about a 19-year-old story - you work in news, you puffed up little s...," she told a television reporter.
Internet-Mana Party leader Laila Harre said Corkery had apologised for losing her cool with the media.
Journalists had pursued Corkery for some time in "quite an aggressive way" for an interview with Dotcom, which they knew before the event they wouldn't be given, Harre said.
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